From d67e26398986057ed426be69701fd7148c94f04b Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Wed, 3 Dec 2014 07:47:08 +0100
Subject: [PATCH 1/6] Remove std::.

---
 libsolidity/Parser.cpp | 34 ++++++++++++++++++----------------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/libsolidity/Parser.cpp b/libsolidity/Parser.cpp
index 0506bc3e3..2a76a05a8 100644
--- a/libsolidity/Parser.cpp
+++ b/libsolidity/Parser.cpp
@@ -26,12 +26,14 @@
 #include <libsolidity/Scanner.h>
 #include <libsolidity/Exceptions.h>
 
+using namespace std;
+
 namespace dev
 {
 namespace solidity
 {
 
-ASTPointer<ContractDefinition> Parser::parse(std::shared_ptr<Scanner> const& _scanner)
+ASTPointer<ContractDefinition> Parser::parse(shared_ptr<Scanner> const& _scanner)
 {
 	m_scanner = _scanner;
 	return parseContractDefinition();
@@ -55,7 +57,7 @@ public:
 	{
 		if (m_location.end < 0)
 			markEndPosition();
-		return std::make_shared<NodeType>(m_location, std::forward<Args>(_args)...);
+		return make_shared<NodeType>(m_location, forward<Args>(_args)...);
 	}
 
 private:
@@ -79,9 +81,9 @@ ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 	expectToken(Token::CONTRACT);
 	ASTPointer<ASTString> name = expectIdentifierToken();
 	expectToken(Token::LBRACE);
-	std::vector<ASTPointer<StructDefinition>> structs;
-	std::vector<ASTPointer<VariableDeclaration>> stateVariables;
-	std::vector<ASTPointer<FunctionDefinition>> functions;
+	vector<ASTPointer<StructDefinition>> structs;
+	vector<ASTPointer<VariableDeclaration>> stateVariables;
+	vector<ASTPointer<FunctionDefinition>> functions;
 	bool visibilityIsPublic = true;
 	while (true)
 	{
@@ -119,7 +121,7 @@ ASTPointer<FunctionDefinition> Parser::parseFunctionDefinition(bool _isPublic)
 	ASTNodeFactory nodeFactory(*this);
 	ASTPointer<ASTString> docstring;
 	if (m_scanner->getCurrentCommentLiteral() != "")
-		docstring = std::make_shared<ASTString>(m_scanner->getCurrentCommentLiteral());
+		docstring = make_shared<ASTString>(m_scanner->getCurrentCommentLiteral());
 
 	expectToken(Token::FUNCTION);
 	ASTPointer<ASTString> name(expectIdentifierToken());
@@ -142,7 +144,7 @@ ASTPointer<FunctionDefinition> Parser::parseFunctionDefinition(bool _isPublic)
 		// create an empty parameter list at a zero-length location
 		ASTNodeFactory nodeFactory(*this);
 		nodeFactory.setLocationEmpty();
-		returnParameters = nodeFactory.createNode<ParameterList>(std::vector<ASTPointer<VariableDeclaration>>());
+		returnParameters = nodeFactory.createNode<ParameterList>(vector<ASTPointer<VariableDeclaration>>());
 	}
 	ASTPointer<Block> block = parseBlock();
 	nodeFactory.setEndPositionFromNode(block);
@@ -156,7 +158,7 @@ ASTPointer<StructDefinition> Parser::parseStructDefinition()
 	ASTNodeFactory nodeFactory(*this);
 	expectToken(Token::STRUCT);
 	ASTPointer<ASTString> name = expectIdentifierToken();
-	std::vector<ASTPointer<VariableDeclaration>> members;
+	vector<ASTPointer<VariableDeclaration>> members;
 	expectToken(Token::LBRACE);
 	while (m_scanner->getCurrentToken() != Token::RBRACE)
 	{
@@ -228,7 +230,7 @@ ASTPointer<Mapping> Parser::parseMapping()
 ASTPointer<ParameterList> Parser::parseParameterList(bool _allowEmpty)
 {
 	ASTNodeFactory nodeFactory(*this);
-	std::vector<ASTPointer<VariableDeclaration>> parameters;
+	vector<ASTPointer<VariableDeclaration>> parameters;
 	expectToken(Token::LPAREN);
 	if (!_allowEmpty || m_scanner->getCurrentToken() != Token::RPAREN)
 	{
@@ -249,7 +251,7 @@ ASTPointer<Block> Parser::parseBlock()
 {
 	ASTNodeFactory nodeFactory(*this);
 	expectToken(Token::LBRACE);
-	std::vector<ASTPointer<Statement>> statements;
+	vector<ASTPointer<Statement>> statements;
 	while (m_scanner->getCurrentToken() != Token::RBRACE)
 		statements.push_back(parseStatement());
 	nodeFactory.markEndPosition();
@@ -447,7 +449,7 @@ ASTPointer<Expression> Parser::parseLeftHandSideExpression()
 		case Token::LPAREN:
 		{
 			m_scanner->next();
-			std::vector<ASTPointer<Expression>> arguments = parseFunctionCallArguments();
+			vector<ASTPointer<Expression>> arguments = parseFunctionCallArguments();
 			nodeFactory.markEndPosition();
 			expectToken(Token::RPAREN);
 			expression = nodeFactory.createNode<FunctionCall>(expression, arguments);
@@ -503,9 +505,9 @@ ASTPointer<Expression> Parser::parsePrimaryExpression()
 	return expression;
 }
 
-std::vector<ASTPointer<Expression>> Parser::parseFunctionCallArguments()
+vector<ASTPointer<Expression>> Parser::parseFunctionCallArguments()
 {
-	std::vector<ASTPointer<Expression>> arguments;
+	vector<ASTPointer<Expression>> arguments;
 	if (m_scanner->getCurrentToken() != Token::RPAREN)
 	{
 		arguments.push_back(parseExpression());
@@ -521,7 +523,7 @@ std::vector<ASTPointer<Expression>> Parser::parseFunctionCallArguments()
 void Parser::expectToken(Token::Value _value)
 {
 	if (m_scanner->getCurrentToken() != _value)
-		BOOST_THROW_EXCEPTION(createParserError(std::string("Expected token ") + std::string(Token::getName(_value))));
+		BOOST_THROW_EXCEPTION(createParserError(string("Expected token ") + string(Token::getName(_value))));
 	m_scanner->next();
 }
 
@@ -543,12 +545,12 @@ ASTPointer<ASTString> Parser::expectIdentifierToken()
 
 ASTPointer<ASTString> Parser::getLiteralAndAdvance()
 {
-	ASTPointer<ASTString> identifier = std::make_shared<ASTString>(m_scanner->getCurrentLiteral());
+	ASTPointer<ASTString> identifier = make_shared<ASTString>(m_scanner->getCurrentLiteral());
 	m_scanner->next();
 	return identifier;
 }
 
-ParserError Parser::createParserError(std::string const& _description) const
+ParserError Parser::createParserError(string const& _description) const
 {
 	return ParserError() << errinfo_sourcePosition(getPosition()) << errinfo_comment(_description);
 }

From 86219490674ca67b7c1b365be1b63a0a81079195 Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Wed, 3 Dec 2014 07:46:55 +0100
Subject: [PATCH 2/6] Import directive.

---
 libsolidity/AST.cpp                    | 69 +++++++++++---------
 libsolidity/AST.h                      | 34 ++++++++++
 libsolidity/ASTForward.h               |  2 +
 libsolidity/ASTPrinter.cpp             |  9 ++-
 libsolidity/ASTPrinter.h               |  3 +-
 libsolidity/ASTVisitor.h               |  4 ++
 libsolidity/CompilerStack.cpp          | 87 +++++++++++++++-----------
 libsolidity/CompilerStack.h            |  5 +-
 libsolidity/Parser.cpp                 | 43 ++++++++++---
 libsolidity/Parser.h                   |  3 +-
 solc/main.cpp                          |  2 +-
 test/solidityCompiler.cpp              | 26 +++++---
 test/solidityExpressionCompiler.cpp    | 47 +++++++-------
 test/solidityNameAndTypeResolution.cpp | 11 ++--
 test/solidityParser.cpp                | 55 +++++++++++++++-
 15 files changed, 285 insertions(+), 115 deletions(-)

diff --git a/libsolidity/AST.cpp b/libsolidity/AST.cpp
index 4bd0b2c0e..697ffe8e3 100644
--- a/libsolidity/AST.cpp
+++ b/libsolidity/AST.cpp
@@ -33,6 +33,19 @@ namespace dev
 namespace solidity
 {
 
+void SourceUnit::accept(ASTVisitor& _visitor)
+{
+	if (_visitor.visit(*this))
+		listAccept(m_nodes, _visitor);
+	_visitor.endVisit(*this);
+}
+
+void ImportDirective::accept(ASTVisitor& _visitor)
+{
+	_visitor.visit(*this);
+	_visitor.endVisit(*this);
+}
+
 void ContractDefinition::accept(ASTVisitor& _visitor)
 {
 	if (_visitor.visit(*this))
@@ -57,34 +70,6 @@ void StructDefinition::checkValidityOfMembers()
 	checkRecursion();
 }
 
-void StructDefinition::checkMemberTypes()
-{
-	for (ASTPointer<VariableDeclaration> const& member: getMembers())
-		if (!member->getType()->canBeStored())
-			BOOST_THROW_EXCEPTION(member->createTypeError("Type cannot be used in struct."));
-}
-
-void StructDefinition::checkRecursion()
-{
-	set<StructDefinition const*> definitionsSeen;
-	vector<StructDefinition const*> queue = {this};
-	while (!queue.empty())
-	{
-		StructDefinition const* def = queue.back();
-		queue.pop_back();
-		if (definitionsSeen.count(def))
-			BOOST_THROW_EXCEPTION(ParserError() << errinfo_sourceLocation(def->getLocation())
-												<< errinfo_comment("Recursive struct definition."));
-		definitionsSeen.insert(def);
-		for (ASTPointer<VariableDeclaration> const& member: def->getMembers())
-			if (member->getType()->getCategory() == Type::Category::STRUCT)
-			{
-				UserDefinedTypeName const& typeName = dynamic_cast<UserDefinedTypeName&>(*member->getTypeName());
-				queue.push_back(&dynamic_cast<StructDefinition const&>(*typeName.getReferencedDeclaration()));
-			}
-	}
-}
-
 void ParameterList::accept(ASTVisitor& _visitor)
 {
 	if (_visitor.visit(*this))
@@ -312,6 +297,34 @@ vector<FunctionDefinition const*> ContractDefinition::getInterfaceFunctions() co
 	return exportedFunctions;
 }
 
+void StructDefinition::checkMemberTypes()
+{
+	for (ASTPointer<VariableDeclaration> const& member: getMembers())
+		if (!member->getType()->canBeStored())
+			BOOST_THROW_EXCEPTION(member->createTypeError("Type cannot be used in struct."));
+}
+
+void StructDefinition::checkRecursion()
+{
+	set<StructDefinition const*> definitionsSeen;
+	vector<StructDefinition const*> queue = {this};
+	while (!queue.empty())
+	{
+		StructDefinition const* def = queue.back();
+		queue.pop_back();
+		if (definitionsSeen.count(def))
+			BOOST_THROW_EXCEPTION(ParserError() << errinfo_sourceLocation(def->getLocation())
+												<< errinfo_comment("Recursive struct definition."));
+		definitionsSeen.insert(def);
+		for (ASTPointer<VariableDeclaration> const& member: def->getMembers())
+			if (member->getType()->getCategory() == Type::Category::STRUCT)
+			{
+				UserDefinedTypeName const& typeName = dynamic_cast<UserDefinedTypeName&>(*member->getTypeName());
+				queue.push_back(&dynamic_cast<StructDefinition const&>(*typeName.getReferencedDeclaration()));
+			}
+	}
+}
+
 void FunctionDefinition::checkTypeRequirements()
 {
 	for (ASTPointer<VariableDeclaration> const& var: getParameters() + getReturnParameters())
diff --git a/libsolidity/AST.h b/libsolidity/AST.h
index 87bc3cd40..2b532d763 100644
--- a/libsolidity/AST.h
+++ b/libsolidity/AST.h
@@ -79,6 +79,40 @@ private:
 	Location m_location;
 };
 
+/**
+ * Source unit containing import directives and contract definitions.
+ */
+class SourceUnit: public ASTNode
+{
+public:
+	SourceUnit(Location const& _location, std::vector<ASTPointer<ASTNode>> const& _nodes):
+		ASTNode(_location), m_nodes(_nodes) {}
+
+	virtual void accept(ASTVisitor& _visitor) override;
+
+	std::vector<ASTPointer<ASTNode>> getNodes() const { return m_nodes; }
+
+private:
+	std::vector<ASTPointer<ASTNode>> m_nodes;
+};
+
+/**
+ * Import directive for referencing other files / source objects.
+ */
+class ImportDirective: public ASTNode
+{
+public:
+	ImportDirective(Location const& _location, ASTPointer<ASTString> const& _url):
+		ASTNode(_location), m_url(_url) {}
+
+	virtual void accept(ASTVisitor& _visitor) override;
+
+	ASTString const& getURL() const { return *m_url; }
+
+private:
+	ASTPointer<ASTString> m_url;
+};
+
 /**
  * Abstract AST class for a declaration (contract, function, struct, variable).
  */
diff --git a/libsolidity/ASTForward.h b/libsolidity/ASTForward.h
index a369c8a79..8b4bac1ce 100644
--- a/libsolidity/ASTForward.h
+++ b/libsolidity/ASTForward.h
@@ -34,6 +34,8 @@ namespace solidity
 {
 
 class ASTNode;
+class SourceUnit;
+class ImportDirective;
 class Declaration;
 class ContractDefinition;
 class StructDefinition;
diff --git a/libsolidity/ASTPrinter.cpp b/libsolidity/ASTPrinter.cpp
index 987ad11cc..c62378fd3 100644
--- a/libsolidity/ASTPrinter.cpp
+++ b/libsolidity/ASTPrinter.cpp
@@ -43,6 +43,13 @@ void ASTPrinter::print(ostream& _stream)
 }
 
 
+bool ASTPrinter::visit(ImportDirective& _node)
+{
+	writeLine("ImportDirective \"" + _node.getURL() + "\"");
+	printSourcePart(_node);
+	return goDeeper();
+}
+
 bool ASTPrinter::visit(ContractDefinition& _node)
 {
 	writeLine("ContractDefinition \"" + _node.getName() + "\"");
@@ -270,7 +277,7 @@ bool ASTPrinter::visit(Literal& _node)
 	return goDeeper();
 }
 
-void ASTPrinter::endVisit(ASTNode&)
+void ASTPrinter::endVisit(ImportDirective&)
 {
 	m_indentation--;
 }
diff --git a/libsolidity/ASTPrinter.h b/libsolidity/ASTPrinter.h
index e0757fbc4..1a18fc4a1 100644
--- a/libsolidity/ASTPrinter.h
+++ b/libsolidity/ASTPrinter.h
@@ -42,6 +42,7 @@ public:
 	/// Output the string representation of the AST to _stream.
 	void print(std::ostream& _stream);
 
+	bool visit(ImportDirective& _node) override;
 	bool visit(ContractDefinition& _node) override;
 	bool visit(StructDefinition& _node) override;
 	bool visit(ParameterList& _node) override;
@@ -73,7 +74,7 @@ public:
 	bool visit(ElementaryTypeNameExpression& _node) override;
 	bool visit(Literal& _node) override;
 
-	void endVisit(ASTNode& _node) override;
+	void endVisit(ImportDirective&) override;
 	void endVisit(ContractDefinition&) override;
 	void endVisit(StructDefinition&) override;
 	void endVisit(ParameterList&) override;
diff --git a/libsolidity/ASTVisitor.h b/libsolidity/ASTVisitor.h
index 6e579f358..bf1ccc410 100644
--- a/libsolidity/ASTVisitor.h
+++ b/libsolidity/ASTVisitor.h
@@ -42,6 +42,8 @@ class ASTVisitor
 {
 public:
 	virtual bool visit(ASTNode&) { return true; }
+	virtual bool visit(SourceUnit&) { return true; }
+	virtual bool visit(ImportDirective&) { return true; }
 	virtual bool visit(ContractDefinition&) { return true; }
 	virtual bool visit(StructDefinition&) { return true; }
 	virtual bool visit(ParameterList&) { return true; }
@@ -74,6 +76,8 @@ public:
 	virtual bool visit(Literal&) { return true; }
 
 	virtual void endVisit(ASTNode&) { }
+	virtual void endVisit(SourceUnit&) { }
+	virtual void endVisit(ImportDirective&) { }
 	virtual void endVisit(ContractDefinition&) { }
 	virtual void endVisit(StructDefinition&) { }
 	virtual void endVisit(ParameterList&) { }
diff --git a/libsolidity/CompilerStack.cpp b/libsolidity/CompilerStack.cpp
index 6535e00d4..8f8c84fea 100644
--- a/libsolidity/CompilerStack.cpp
+++ b/libsolidity/CompilerStack.cpp
@@ -45,10 +45,14 @@ void CompilerStack::parse()
 {
 	if (!m_scanner)
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Source not available."));
-	m_contractASTNode = Parser().parse(m_scanner);
+	m_sourceUnitASTNode = Parser().parse(m_scanner);
 	m_globalContext = make_shared<GlobalContext>();
-	m_globalContext->setCurrentContract(*m_contractASTNode);
-	NameAndTypeResolver(m_globalContext->getDeclarations()).resolveNamesAndTypes(*m_contractASTNode);
+	for (ASTPointer<ASTNode> const& node: m_sourceUnitASTNode->getNodes())
+		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			m_globalContext->setCurrentContract(*contract);
+			NameAndTypeResolver(m_globalContext->getDeclarations()).resolveNamesAndTypes(*contract);
+		}
 	m_parseSuccessful = true;
 }
 
@@ -62,10 +66,16 @@ bytes const& CompilerStack::compile(bool _optimize)
 {
 	if (!m_parseSuccessful)
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
-	m_bytecode.clear();
-	m_compiler = make_shared<Compiler>();
-	m_compiler->compileContract(*m_contractASTNode, m_globalContext->getMagicVariables());
-	return m_bytecode = m_compiler->getAssembledBytecode(_optimize);
+	//@todo returns only the last contract for now
+	for (ASTPointer<ASTNode> const& node: m_sourceUnitASTNode->getNodes())
+		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			m_bytecode.clear();
+			m_compiler = make_shared<Compiler>();
+			m_compiler->compileContract(*contract, m_globalContext->getMagicVariables());
+			m_bytecode = m_compiler->getAssembledBytecode(_optimize);
+		}
+	return m_bytecode;
 }
 
 bytes const& CompilerStack::compile(string const& _sourceCode, bool _optimize)
@@ -87,40 +97,45 @@ string const& CompilerStack::getInterface()
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
 	if (m_interface.empty())
 	{
-		stringstream interface;
-		interface << '[';
-		vector<FunctionDefinition const*> exportedFunctions = m_contractASTNode->getInterfaceFunctions();
-		unsigned functionsCount = exportedFunctions.size();
-		for (FunctionDefinition const* f: exportedFunctions)
-		{
-			auto streamVariables = [&](vector<ASTPointer<VariableDeclaration>> const& _vars)
+		//@todo returns only the last contract for now
+		for (ASTPointer<ASTNode> const& node: m_sourceUnitASTNode->getNodes())
+			if (ContractDefinition const* contract = dynamic_cast<ContractDefinition*>(node.get()))
 			{
-				unsigned varCount = _vars.size();
-				for (ASTPointer<VariableDeclaration> const& var: _vars)
+				stringstream interface;
+				interface << '[';
+				vector<FunctionDefinition const*> exportedFunctions = contract->getInterfaceFunctions();
+				unsigned functionsCount = exportedFunctions.size();
+				for (FunctionDefinition const* f: exportedFunctions)
 				{
-					interface << "{"
-							  << "\"name\":" << escaped(var->getName(), false) << ","
-							  << "\"type\":" << escaped(var->getType()->toString(), false)
+					auto streamVariables = [&](vector<ASTPointer<VariableDeclaration>> const& _vars)
+					{
+						unsigned varCount = _vars.size();
+						for (ASTPointer<VariableDeclaration> const& var: _vars)
+						{
+							interface << "{"
+									  << "\"name\":" << escaped(var->getName(), false) << ","
+									  << "\"type\":" << escaped(var->getType()->toString(), false)
+									  << "}";
+							if (--varCount > 0)
+								interface << ",";
+						}
+					};
+
+					interface << '{'
+							  << "\"name\":" << escaped(f->getName(), false) << ","
+							  << "\"inputs\":[";
+					streamVariables(f->getParameters());
+					interface << "],"
+							  << "\"outputs\":[";
+					streamVariables(f->getReturnParameters());
+					interface << "]"
 							  << "}";
-					if (--varCount > 0)
+					if (--functionsCount > 0)
 						interface << ",";
 				}
-			};
-
-			interface << '{'
-					  << "\"name\":" << escaped(f->getName(), false) << ","
-					  << "\"inputs\":[";
-			streamVariables(f->getParameters());
-			interface << "],"
-					  << "\"outputs\":[";
-			streamVariables(f->getReturnParameters());
-			interface << "]"
-					  << "}";
-			if (--functionsCount > 0)
-				interface << ",";
-		}
-		interface << ']';
-		m_interface = interface.str();
+				interface << ']';
+				m_interface = interface.str();
+			}
 	}
 	return m_interface;
 }
diff --git a/libsolidity/CompilerStack.h b/libsolidity/CompilerStack.h
index 6cae8660f..19f3cf99a 100644
--- a/libsolidity/CompilerStack.h
+++ b/libsolidity/CompilerStack.h
@@ -32,6 +32,7 @@ namespace solidity {
 
 // forward declarations
 class Scanner;
+class SourceUnit;
 class ContractDefinition;
 class Compiler;
 class GlobalContext;
@@ -65,7 +66,7 @@ public:
 
 	/// Returns the previously used scanner, useful for counting lines during error reporting.
 	Scanner const& getScanner() const { return *m_scanner; }
-	ContractDefinition& getAST() const { return *m_contractASTNode; }
+	SourceUnit& getAST() const { return *m_sourceUnitASTNode; }
 
 	/// Compile the given @a _sourceCode to bytecode. If a scanner is provided, it is used for
 	/// scanning the source code - this is useful for printing exception information.
@@ -74,7 +75,7 @@ public:
 private:
 	std::shared_ptr<Scanner> m_scanner;
 	std::shared_ptr<GlobalContext> m_globalContext;
-	std::shared_ptr<ContractDefinition> m_contractASTNode;
+	std::shared_ptr<SourceUnit> m_sourceUnitASTNode;
 	bool m_parseSuccessful;
 	std::string m_interface;
 	std::shared_ptr<Compiler> m_compiler;
diff --git a/libsolidity/Parser.cpp b/libsolidity/Parser.cpp
index 2a76a05a8..c385dd8d1 100644
--- a/libsolidity/Parser.cpp
+++ b/libsolidity/Parser.cpp
@@ -20,6 +20,7 @@
  * Solidity parser.
  */
 
+#include <vector>
 #include <libdevcore/Log.h>
 #include <libsolidity/BaseTypes.h>
 #include <libsolidity/Parser.h>
@@ -33,13 +34,6 @@ namespace dev
 namespace solidity
 {
 
-ASTPointer<ContractDefinition> Parser::parse(shared_ptr<Scanner> const& _scanner)
-{
-	m_scanner = _scanner;
-	return parseContractDefinition();
-}
-
-
 /// AST node factory that also tracks the begin and end position of an AST node
 /// while it is being parsed
 class Parser::ASTNodeFactory
@@ -65,6 +59,28 @@ private:
 	Location m_location;
 };
 
+ASTPointer<SourceUnit> Parser::parse(shared_ptr<Scanner> const& _scanner)
+{
+	m_scanner = _scanner;
+	ASTNodeFactory nodeFactory(*this);
+	vector<ASTPointer<ASTNode>> nodes;
+	while (_scanner->getCurrentToken() != Token::EOS)
+	{
+		switch (m_scanner->getCurrentToken())
+		{
+		case Token::IMPORT:
+			nodes.push_back(parseImportDirective());
+			break;
+		case Token::CONTRACT:
+			nodes.push_back(parseContractDefinition());
+			break;
+		default:
+			BOOST_THROW_EXCEPTION(createParserError(std::string("Expected import directive or contract definition.")));
+		}
+	}
+	return nodeFactory.createNode<SourceUnit>(nodes);
+}
+
 int Parser::getPosition() const
 {
 	return m_scanner->getCurrentLocation().start;
@@ -75,6 +91,18 @@ int Parser::getEndPosition() const
 	return m_scanner->getCurrentLocation().end;
 }
 
+ASTPointer<ImportDirective> Parser::parseImportDirective()
+{
+	ASTNodeFactory nodeFactory(*this);
+	expectToken(Token::IMPORT);
+	if (m_scanner->getCurrentToken() != Token::STRING_LITERAL)
+		BOOST_THROW_EXCEPTION(createParserError("Expected string literal (URL)."));
+	ASTPointer<ASTString> url = getLiteralAndAdvance();
+	nodeFactory.markEndPosition();
+	expectToken(Token::SEMICOLON);
+	return nodeFactory.createNode<ImportDirective>(url);
+}
+
 ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 {
 	ASTNodeFactory nodeFactory(*this);
@@ -112,7 +140,6 @@ ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 	}
 	nodeFactory.markEndPosition();
 	expectToken(Token::RBRACE);
-	expectToken(Token::EOS);
 	return nodeFactory.createNode<ContractDefinition>(name, structs, stateVariables, functions);
 }
 
diff --git a/libsolidity/Parser.h b/libsolidity/Parser.h
index 307a0d6a1..98a337b29 100644
--- a/libsolidity/Parser.h
+++ b/libsolidity/Parser.h
@@ -34,7 +34,7 @@ class Scanner;
 class Parser
 {
 public:
-	ASTPointer<ContractDefinition> parse(std::shared_ptr<Scanner> const& _scanner);
+	ASTPointer<SourceUnit> parse(std::shared_ptr<Scanner> const& _scanner);
 
 private:
 	class ASTNodeFactory;
@@ -46,6 +46,7 @@ private:
 
 	///@{
 	///@name Parsing functions for the AST nodes
+	ASTPointer<ImportDirective> parseImportDirective();
 	ASTPointer<ContractDefinition> parseContractDefinition();
 	ASTPointer<FunctionDefinition> parseFunctionDefinition(bool _isPublic);
 	ASTPointer<StructDefinition> parseStructDefinition();
diff --git a/solc/main.cpp b/solc/main.cpp
index a7216e594..76d8ef6b7 100644
--- a/solc/main.cpp
+++ b/solc/main.cpp
@@ -127,7 +127,7 @@ int main(int argc, char** argv)
 		return -1;
 	}
 
-	cout << "Syntax tree for the contract:" << endl;
+	cout << "Syntax tree for the source unit:" << endl;
 	ASTPrinter printer(compiler.getAST(), sourceCode);
 	printer.print(cout);
 	cout << "EVM assembly:" << endl;
diff --git a/test/solidityCompiler.cpp b/test/solidityCompiler.cpp
index 3e86919a6..883cecf28 100644
--- a/test/solidityCompiler.cpp
+++ b/test/solidityCompiler.cpp
@@ -46,16 +46,22 @@ namespace
 bytes compileContract(const string& _sourceCode)
 {
 	Parser parser;
-	ASTPointer<ContractDefinition> contract;
-	BOOST_REQUIRE_NO_THROW(contract = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
-	NameAndTypeResolver resolver({});
-	BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
-
-	Compiler compiler;
-	compiler.compileContract(*contract, {});
-	// debug
-	//compiler.streamAssembly(cout);
-	return compiler.getAssembledBytecode();
+	ASTPointer<SourceUnit> sourceUnit;
+	BOOST_REQUIRE_NO_THROW(sourceUnit = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
+	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
+		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			NameAndTypeResolver resolver({});
+			BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
+
+			Compiler compiler;
+			compiler.compileContract(*contract, {});
+			// debug
+			//compiler.streamAssembly(cout);
+			return compiler.getAssembledBytecode();
+		}
+	BOOST_FAIL("No contract found in source.");
+	return bytes();
 }
 
 /// Checks that @a _compiledCode is present starting from offset @a _offset in @a _expectation.
diff --git a/test/solidityExpressionCompiler.cpp b/test/solidityExpressionCompiler.cpp
index 6ea66badb..b077e2620 100644
--- a/test/solidityExpressionCompiler.cpp
+++ b/test/solidityExpressionCompiler.cpp
@@ -86,27 +86,32 @@ bytes compileFirstExpression(const string& _sourceCode, vector<vector<string>> _
 							 vector<vector<string>> _localVariables = {})
 {
 	Parser parser;
-	ASTPointer<ContractDefinition> contract;
-	BOOST_REQUIRE_NO_THROW(contract = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
-	NameAndTypeResolver resolver({});
-	BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
-	FirstExpressionExtractor extractor(*contract);
-	BOOST_REQUIRE(extractor.getExpression() != nullptr);
-
-	CompilerContext context;
-	for (vector<string> const& function: _functions)
-		context.addFunction(dynamic_cast<FunctionDefinition const&>(resolveDeclaration(function, resolver)));
-	for (vector<string> const& variable: _localVariables)
-		context.addVariable(dynamic_cast<VariableDeclaration const&>(resolveDeclaration(variable, resolver)));
-
-	ExpressionCompiler::compileExpression(context, *extractor.getExpression());
-
-	for (vector<string> const& function: _functions)
-		context << context.getFunctionEntryLabel(dynamic_cast<FunctionDefinition const&>(resolveDeclaration(function, resolver)));
-	bytes instructions = context.getAssembledBytecode();
-	// debug
-	// cout << eth::disassemble(instructions) << endl;
-	return instructions;
+	ASTPointer<SourceUnit> sourceUnit;
+	BOOST_REQUIRE_NO_THROW(sourceUnit = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
+	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
+		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			NameAndTypeResolver resolver({});
+			BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
+			FirstExpressionExtractor extractor(*contract);
+			BOOST_REQUIRE(extractor.getExpression() != nullptr);
+
+			CompilerContext context;
+			for (vector<string> const& function: _functions)
+				context.addFunction(dynamic_cast<FunctionDefinition const&>(resolveDeclaration(function, resolver)));
+			for (vector<string> const& variable: _localVariables)
+				context.addVariable(dynamic_cast<VariableDeclaration const&>(resolveDeclaration(variable, resolver)));
+
+			ExpressionCompiler::compileExpression(context, *extractor.getExpression());
+
+			for (vector<string> const& function: _functions)
+				context << context.getFunctionEntryLabel(dynamic_cast<FunctionDefinition const&>(resolveDeclaration(function, resolver)));
+			bytes instructions = context.getAssembledBytecode();
+			// debug
+			// cout << eth::disassemble(instructions) << endl;
+			return instructions;
+		}
+	BOOST_FAIL("No contract found in source.");
 }
 
 } // end anonymous namespace
diff --git a/test/solidityNameAndTypeResolution.cpp b/test/solidityNameAndTypeResolution.cpp
index 8804c519c..219fa2599 100644
--- a/test/solidityNameAndTypeResolution.cpp
+++ b/test/solidityNameAndTypeResolution.cpp
@@ -41,10 +41,13 @@ namespace
 void parseTextAndResolveNames(std::string const& _source)
 {
 	Parser parser;
-	ASTPointer<ContractDefinition> contract = parser.parse(
-										   std::make_shared<Scanner>(CharStream(_source)));
-	NameAndTypeResolver resolver({});
-	resolver.resolveNamesAndTypes(*contract);
+	ASTPointer<SourceUnit> sourceUnit = parser.parse(std::make_shared<Scanner>(CharStream(_source)));
+	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
+		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		{
+			NameAndTypeResolver resolver({});
+			resolver.resolveNamesAndTypes(*contract);
+		}
 }
 }
 
diff --git a/test/solidityParser.cpp b/test/solidityParser.cpp
index 6a97a5d99..a9e2d531f 100644
--- a/test/solidityParser.cpp
+++ b/test/solidityParser.cpp
@@ -21,13 +21,15 @@
  */
 
 #include <string>
-
+#include <memory>
 #include <libdevcore/Log.h>
 #include <libsolidity/Scanner.h>
 #include <libsolidity/Parser.h>
 #include <libsolidity/Exceptions.h>
 #include <boost/test/unit_test.hpp>
 
+using namespace std;
+
 namespace dev
 {
 namespace solidity
@@ -40,7 +42,12 @@ namespace
 ASTPointer<ContractDefinition> parseText(std::string const& _source)
 {
 	Parser parser;
-	return parser.parse(std::make_shared<Scanner>(CharStream(_source)));
+	ASTPointer<SourceUnit> sourceUnit = parser.parse(std::make_shared<Scanner>(CharStream(_source)));
+	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
+		if (ASTPointer<ContractDefinition> contract = dynamic_pointer_cast<ContractDefinition>(node))
+			return contract;
+	BOOST_FAIL("No contract found in source.");
+	return ASTPointer<ContractDefinition>();
 }
 }
 
@@ -380,6 +387,50 @@ BOOST_AUTO_TEST_CASE(statement_starting_with_type_conversion)
 	BOOST_CHECK_NO_THROW(parseText(text));
 }
 
+BOOST_AUTO_TEST_CASE(import_directive)
+{
+	char const* text = "import \"abc\";\n"
+					   "contract test {\n"
+					   "  function fun() {\n"
+					   "    uint64(2);\n"
+					   "  }\n"
+					   "}\n";
+	BOOST_CHECK_NO_THROW(parseText(text));
+}
+
+BOOST_AUTO_TEST_CASE(multiple_contracts)
+{
+	char const* text = "contract test {\n"
+					   "  function fun() {\n"
+					   "    uint64(2);\n"
+					   "  }\n"
+					   "}\n"
+					   "contract test2 {\n"
+					   "  function fun() {\n"
+					   "    uint64(2);\n"
+					   "  }\n"
+					   "}\n";
+	BOOST_CHECK_NO_THROW(parseText(text));
+}
+
+BOOST_AUTO_TEST_CASE(multiple_contracts_and_imports)
+{
+	char const* text = "import \"abc\";\n"
+					   "contract test {\n"
+					   "  function fun() {\n"
+					   "    uint64(2);\n"
+					   "  }\n"
+					   "}\n"
+					   "import \"def\";\n"
+					   "contract test2 {\n"
+					   "  function fun() {\n"
+					   "    uint64(2);\n"
+					   "  }\n"
+					   "}\n"
+					   "import \"ghi\";\n";
+	BOOST_CHECK_NO_THROW(parseText(text));
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }

From 50b61e3dd390aa5bcabe8ad0d30dc00792443b90 Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Wed, 3 Dec 2014 17:45:12 +0100
Subject: [PATCH 3/6] Multi-source and multi-contract compiler.

---
 libsolidity/BaseTypes.h                |   7 +-
 libsolidity/CompilerStack.cpp          | 219 +++++++++++++++++--------
 libsolidity/CompilerStack.h            |  61 +++++--
 libsolidity/DeclarationContainer.cpp   |   4 +-
 libsolidity/DeclarationContainer.h     |   2 +-
 libsolidity/GlobalContext.cpp          |   3 +-
 libsolidity/GlobalContext.h            |   3 +-
 libsolidity/NameAndTypeResolver.cpp    |  12 +-
 libsolidity/NameAndTypeResolver.h      |   6 +
 libsolidity/Scanner.cpp                |  17 +-
 libsolidity/Scanner.h                  |  11 +-
 test/solidityCompiler.cpp              |   3 +-
 test/solidityExpressionCompiler.cpp    |   3 +-
 test/solidityNameAndTypeResolution.cpp |   3 +-
 14 files changed, 254 insertions(+), 100 deletions(-)

diff --git a/libsolidity/BaseTypes.h b/libsolidity/BaseTypes.h
index d1ffd7bbc..627aa7dfd 100644
--- a/libsolidity/BaseTypes.h
+++ b/libsolidity/BaseTypes.h
@@ -22,6 +22,8 @@
 
 #pragma once
 
+#include <memory>
+#include <string>
 #include <ostream>
 
 namespace dev
@@ -38,8 +40,9 @@ struct Location
 	Location(int _start, int _end): start(_start), end(_end) { }
 	Location(): start(-1), end(-1) { }
 
-	bool IsValid() const { return start >= 0 && end >= start; }
+	bool IsValid() const { return !!sourceName && start >= 0 && end >= start; }
 
+	std::shared_ptr<std::string> sourceName;
 	int start;
 	int end;
 };
@@ -47,7 +50,7 @@ struct Location
 /// Stream output for Location (used e.g. in boost exceptions).
 inline std::ostream& operator<<(std::ostream& _out, Location const& _location)
 {
-	return _out << "[" << _location.start << "," << _location.end << ")";
+	return _out << *_location.sourceName << "[" << _location.start << "," << _location.end << ")";
 }
 
 }
diff --git a/libsolidity/CompilerStack.cpp b/libsolidity/CompilerStack.cpp
index 8f8c84fea..49ac3b64c 100644
--- a/libsolidity/CompilerStack.cpp
+++ b/libsolidity/CompilerStack.cpp
@@ -35,24 +35,43 @@ namespace dev
 namespace solidity
 {
 
+void CompilerStack::addSource(string const& _name, string const& _content)
+{
+	if (m_sources.count(_name))
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Source by given name already exists."));
+
+	reset(true);
+	m_sources[_name].scanner = make_shared<Scanner>(CharStream(_content), _name);
+}
+
 void CompilerStack::setSource(string const& _sourceCode)
 {
 	reset();
-	m_scanner = make_shared<Scanner>(CharStream(_sourceCode));
+	addSource("", _sourceCode);
 }
 
 void CompilerStack::parse()
 {
-	if (!m_scanner)
-		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Source not available."));
-	m_sourceUnitASTNode = Parser().parse(m_scanner);
+	for (auto& sourcePair: m_sources)
+	{
+		sourcePair.second.scanner->reset();
+		sourcePair.second.ast = Parser().parse(sourcePair.second.scanner);
+	}
+	resolveImports();
+
 	m_globalContext = make_shared<GlobalContext>();
-	for (ASTPointer<ASTNode> const& node: m_sourceUnitASTNode->getNodes())
-		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
-		{
-			m_globalContext->setCurrentContract(*contract);
-			NameAndTypeResolver(m_globalContext->getDeclarations()).resolveNamesAndTypes(*contract);
-		}
+	NameAndTypeResolver resolver(m_globalContext->getDeclarations());
+	for (Source const* source: m_sourceOrder)
+		resolver.registerDeclarations(*source->ast);
+	for (Source const* source: m_sourceOrder)
+		for (ASTPointer<ASTNode> const& node: source->ast->getNodes())
+			if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+			{
+				m_globalContext->setCurrentContract(*contract);
+				resolver.updateDeclaration(*m_globalContext->getCurrentThis());
+				resolver.resolveNamesAndTypes(*contract);
+				m_contracts[contract->getName()].contract = contract;
+			}
 	m_parseSuccessful = true;
 }
 
@@ -62,82 +81,91 @@ void CompilerStack::parse(string const& _sourceCode)
 	parse();
 }
 
-bytes const& CompilerStack::compile(bool _optimize)
+void CompilerStack::compile(bool _optimize)
 {
 	if (!m_parseSuccessful)
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
-	//@todo returns only the last contract for now
-	for (ASTPointer<ASTNode> const& node: m_sourceUnitASTNode->getNodes())
-		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
-		{
-			m_bytecode.clear();
-			m_compiler = make_shared<Compiler>();
-			m_compiler->compileContract(*contract, m_globalContext->getMagicVariables());
-			m_bytecode = m_compiler->getAssembledBytecode(_optimize);
-		}
-	return m_bytecode;
+	for (Source const* source: m_sourceOrder)
+		for (ASTPointer<ASTNode> const& node: source->ast->getNodes())
+			if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
+			{
+				m_globalContext->setCurrentContract(*contract);
+				shared_ptr<Compiler> compiler = make_shared<Compiler>();
+				compiler->compileContract(*contract, m_globalContext->getMagicVariables());
+				Contract& compiledContract = m_contracts[contract->getName()];
+				compiledContract.bytecode = compiler->getAssembledBytecode(_optimize);
+				compiledContract.compiler = move(compiler);
+			}
 }
 
 bytes const& CompilerStack::compile(string const& _sourceCode, bool _optimize)
 {
 	parse(_sourceCode);
-	return compile(_optimize);
+	compile(_optimize);
+	return getBytecode();
 }
 
-void CompilerStack::streamAssembly(ostream& _outStream)
+bytes const& CompilerStack::getBytecode(string const& _contractName)
 {
-	if (!m_compiler || m_bytecode.empty())
-		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Compilation was not successful."));
-	m_compiler->streamAssembly(_outStream);
+	return getContract(_contractName).bytecode;
 }
 
-string const& CompilerStack::getInterface()
+void CompilerStack::streamAssembly(ostream& _outStream, string const& _contractName)
 {
-	if (!m_parseSuccessful)
-		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
-	if (m_interface.empty())
+	getContract(_contractName).compiler->streamAssembly(_outStream);
+}
+
+string const& CompilerStack::getInterface(std::string const& _contractName)
+{
+	Contract& contract = getContract(_contractName);
+	if (contract.interface.empty())
 	{
-		//@todo returns only the last contract for now
-		for (ASTPointer<ASTNode> const& node: m_sourceUnitASTNode->getNodes())
-			if (ContractDefinition const* contract = dynamic_cast<ContractDefinition*>(node.get()))
+		stringstream interface;
+		interface << '[';
+		vector<FunctionDefinition const*> exportedFunctions = contract.contract->getInterfaceFunctions();
+		unsigned functionsCount = exportedFunctions.size();
+		for (FunctionDefinition const* f: exportedFunctions)
+		{
+			auto streamVariables = [&](vector<ASTPointer<VariableDeclaration>> const& _vars)
 			{
-				stringstream interface;
-				interface << '[';
-				vector<FunctionDefinition const*> exportedFunctions = contract->getInterfaceFunctions();
-				unsigned functionsCount = exportedFunctions.size();
-				for (FunctionDefinition const* f: exportedFunctions)
+				unsigned varCount = _vars.size();
+				for (ASTPointer<VariableDeclaration> const& var: _vars)
 				{
-					auto streamVariables = [&](vector<ASTPointer<VariableDeclaration>> const& _vars)
-					{
-						unsigned varCount = _vars.size();
-						for (ASTPointer<VariableDeclaration> const& var: _vars)
-						{
-							interface << "{"
-									  << "\"name\":" << escaped(var->getName(), false) << ","
-									  << "\"type\":" << escaped(var->getType()->toString(), false)
-									  << "}";
-							if (--varCount > 0)
-								interface << ",";
-						}
-					};
-
-					interface << '{'
-							  << "\"name\":" << escaped(f->getName(), false) << ","
-							  << "\"inputs\":[";
-					streamVariables(f->getParameters());
-					interface << "],"
-							  << "\"outputs\":[";
-					streamVariables(f->getReturnParameters());
-					interface << "]"
+					interface << "{"
+							  << "\"name\":" << escaped(var->getName(), false) << ","
+							  << "\"type\":" << escaped(var->getType()->toString(), false)
 							  << "}";
-					if (--functionsCount > 0)
+					if (--varCount > 0)
 						interface << ",";
 				}
-				interface << ']';
-				m_interface = interface.str();
-			}
+			};
+
+			interface << '{'
+					  << "\"name\":" << escaped(f->getName(), false) << ","
+					  << "\"inputs\":[";
+			streamVariables(f->getParameters());
+			interface << "],"
+					  << "\"outputs\":[";
+			streamVariables(f->getReturnParameters());
+			interface << "]"
+					  << "}";
+			if (--functionsCount > 0)
+				interface << ",";
+		}
+		interface << ']';
+		contract.interface = interface.str();
 	}
-	return m_interface;
+	return contract.interface;
+}
+
+Scanner const& CompilerStack::getScanner(string const& _sourceName)
+{
+	return *getSource(_sourceName).scanner;
+}
+
+SourceUnit& CompilerStack::getAST(string const& _sourceName)
+{
+	return *getSource(_sourceName).ast;
 }
 
 bytes CompilerStack::staticCompile(std::string const& _sourceCode, bool _optimize)
@@ -146,7 +174,68 @@ bytes CompilerStack::staticCompile(std::string const& _sourceCode, bool _optimiz
 	return stack.compile(_sourceCode, _optimize);
 }
 
+void CompilerStack::reset(bool _keepSources)
+{
+	m_parseSuccessful = false;
+	if (_keepSources)
+		for (auto sourcePair: m_sources)
+			sourcePair.second.reset();
+	else
+		m_sources.clear();
+	m_globalContext.reset();
+	m_compiler.reset();
+	m_sourceOrder.clear();
+	m_contracts.clear();
+}
+
+void CompilerStack::resolveImports()
+{
+	// topological sorting (depth first search) of the import graph, cutting potential cycles
+	vector<Source const*> sourceOrder;
+	set<Source const*> sourcesSeen;
+
+	function<void(Source const*)> toposort = [&](Source const* _source)
+	{
+		if (sourcesSeen.count(_source))
+			return;
+		sourcesSeen.insert(_source);
+		for (ASTPointer<ASTNode> const& node: _source->ast->getNodes())
+			if (ImportDirective const* import = dynamic_cast<ImportDirective*>(node.get()))
+			{
+				string const& url = import->getURL();
+				if (!m_sources.count(url))
+					BOOST_THROW_EXCEPTION(ParserError()
+										  << errinfo_sourceLocation(import->getLocation())
+										  << errinfo_comment("Source not found."));
+				toposort(&m_sources[url]);
+			}
+		sourceOrder.push_back(_source);
+	};
+
+	for (auto const& sourcePair: m_sources)
+		toposort(&sourcePair.second);
 
+	swap(m_sourceOrder, sourceOrder);
+}
 
+CompilerStack::Contract& CompilerStack::getContract(string const& _contractName)
+{
+	if (m_contracts.empty())
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("No compiled contracts found."));
+	if (_contractName.empty())
+		return m_contracts.begin()->second;
+	auto it = m_contracts.find(_contractName);
+	if (it == m_contracts.end())
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Contract " + _contractName + " not found."));
+	return it->second;
+}
+
+CompilerStack::Source& CompilerStack::getSource(string const& _sourceName)
+{
+	auto it = m_sources.find(_sourceName);
+	if (it == m_sources.end())
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Given source file not found."));
+	return it->second;
+}
 }
 }
diff --git a/libsolidity/CompilerStack.h b/libsolidity/CompilerStack.h
index 19f3cf99a..0520f2b1b 100644
--- a/libsolidity/CompilerStack.h
+++ b/libsolidity/CompilerStack.h
@@ -25,6 +25,7 @@
 #include <ostream>
 #include <string>
 #include <memory>
+#include <boost/noncopyable.hpp>
 #include <libdevcore/Common.h>
 
 namespace dev {
@@ -33,53 +34,81 @@ namespace solidity {
 // forward declarations
 class Scanner;
 class SourceUnit;
-class ContractDefinition;
 class Compiler;
 class GlobalContext;
+class ContractDefinition;
 
 /**
  * Easy to use and self-contained Solidity compiler with as few header dependencies as possible.
  * It holds state and can be used to either step through the compilation stages (and abort e.g.
  * before compilation to bytecode) or run the whole compilation in one call.
  */
-class CompilerStack
+class CompilerStack: boost::noncopyable
 {
 public:
-	CompilerStack() {}
-	void reset() {  *this = CompilerStack(); }
+	CompilerStack(): m_parseSuccessful(false) {}
+	/// Adds a source object (e.g. file) to the parser. After this, parse has to be called again.
+	void addSource(std::string const& _name, std::string const& _content);
 	void setSource(std::string const& _sourceCode);
+	/// Parses all source units that were added
 	void parse();
+	/// Sets the given source code as the only source unit and parses it.
 	void parse(std::string const& _sourceCode);
-	/// Compiles the contract that was previously parsed.
-	bytes const& compile(bool _optimize = false);
+	/// Compiles the source units that were prevously added and parsed.
+	void compile(bool _optimize = false);
 	/// Parses and compiles the given source code.
+	/// @returns the compiled bytecode
 	bytes const& compile(std::string const& _sourceCode, bool _optimize = false);
 
-	bytes const& getBytecode() const { return m_bytecode; }
+	bytes const& getBytecode(std::string const& _contractName = "");
 	/// Streams a verbose version of the assembly to @a _outStream.
 	/// Prerequisite: Successful compilation.
-	void streamAssembly(std::ostream& _outStream);
+	void streamAssembly(std::ostream& _outStream, std::string const& _contractName = "");
 
 	/// Returns a string representing the contract interface in JSON.
 	/// Prerequisite: Successful call to parse or compile.
-	std::string const& getInterface();
+	std::string const& getInterface(std::string const& _contractName = "");
 
 	/// Returns the previously used scanner, useful for counting lines during error reporting.
-	Scanner const& getScanner() const { return *m_scanner; }
-	SourceUnit& getAST() const { return *m_sourceUnitASTNode; }
+	Scanner const& getScanner(std::string const& _sourceName = "");
+	SourceUnit& getAST(std::string const& _sourceName = "");
 
 	/// Compile the given @a _sourceCode to bytecode. If a scanner is provided, it is used for
 	/// scanning the source code - this is useful for printing exception information.
 	static bytes staticCompile(std::string const& _sourceCode, bool _optimize = false);
 
 private:
-	std::shared_ptr<Scanner> m_scanner;
-	std::shared_ptr<GlobalContext> m_globalContext;
-	std::shared_ptr<SourceUnit> m_sourceUnitASTNode;
+	/**
+	 * Information pertaining to one source unit, filled gradually during parsing and compilation.
+	 */
+	struct Source
+	{
+		std::shared_ptr<Scanner> scanner;
+		std::shared_ptr<SourceUnit> ast;
+		std::string interface;
+		void reset() { scanner.reset(); ast.reset(); interface.clear(); }
+	};
+
+	struct Contract
+	{
+		ContractDefinition const* contract;
+		std::string interface;
+		std::shared_ptr<Compiler> compiler;
+		bytes bytecode;
+	};
+
+	void reset(bool _keepSources = false);
+	void resolveImports();
+
+	Contract& getContract(std::string const& _contractName = "");
+	Source& getSource(std::string const& _sourceName = "");
+
 	bool m_parseSuccessful;
-	std::string m_interface;
+	std::map<std::string, Source> m_sources;
+	std::shared_ptr<GlobalContext> m_globalContext;
 	std::shared_ptr<Compiler> m_compiler;
-	bytes m_bytecode;
+	std::vector<Source const*> m_sourceOrder;
+	std::map<std::string, Contract> m_contracts;
 };
 
 }
diff --git a/libsolidity/DeclarationContainer.cpp b/libsolidity/DeclarationContainer.cpp
index 6ea9c28c5..c0dea757a 100644
--- a/libsolidity/DeclarationContainer.cpp
+++ b/libsolidity/DeclarationContainer.cpp
@@ -28,9 +28,9 @@ namespace dev
 namespace solidity
 {
 
-bool DeclarationContainer::registerDeclaration(Declaration& _declaration)
+bool DeclarationContainer::registerDeclaration(Declaration& _declaration, bool _update)
 {
-	if (m_declarations.find(_declaration.getName()) != m_declarations.end())
+	if (!_update && m_declarations.find(_declaration.getName()) != m_declarations.end())
 		return false;
 	m_declarations[_declaration.getName()] = &_declaration;
 	return true;
diff --git a/libsolidity/DeclarationContainer.h b/libsolidity/DeclarationContainer.h
index db6812890..e1b363e04 100644
--- a/libsolidity/DeclarationContainer.h
+++ b/libsolidity/DeclarationContainer.h
@@ -43,7 +43,7 @@ public:
 		m_enclosingDeclaration(_enclosingDeclaration), m_enclosingContainer(_enclosingContainer) {}
 	/// Registers the declaration in the scope unless its name is already declared. Returns true iff
 	/// it was not yet declared.
-	bool registerDeclaration(Declaration& _declaration);
+	bool registerDeclaration(Declaration& _declaration, bool _update = false);
 	Declaration* resolveName(ASTString const& _name, bool _recursive = false) const;
 	Declaration* getEnclosingDeclaration() const { return m_enclosingDeclaration; }
 
diff --git a/libsolidity/GlobalContext.cpp b/libsolidity/GlobalContext.cpp
index d8b637076..45242bb1f 100644
--- a/libsolidity/GlobalContext.cpp
+++ b/libsolidity/GlobalContext.cpp
@@ -74,11 +74,10 @@ vector<Declaration*> GlobalContext::getDeclarations() const
 	declarations.reserve(m_magicVariables.size() + 1);
 	for (ASTPointer<Declaration> const& variable: m_magicVariables)
 		declarations.push_back(variable.get());
-	declarations.push_back(getCurrentThis());
 	return declarations;
 }
 
-MagicVariableDeclaration*GlobalContext::getCurrentThis() const
+MagicVariableDeclaration* GlobalContext::getCurrentThis() const
 {
 	if (!m_thisPointer[m_currentContract])
 		m_thisPointer[m_currentContract] = make_shared<MagicVariableDeclaration>(
diff --git a/libsolidity/GlobalContext.h b/libsolidity/GlobalContext.h
index 0166734ca..fc3914d2a 100644
--- a/libsolidity/GlobalContext.h
+++ b/libsolidity/GlobalContext.h
@@ -47,12 +47,13 @@ class GlobalContext: private boost::noncopyable
 public:
 	GlobalContext();
 	void setCurrentContract(ContractDefinition const& _contract);
+	MagicVariableDeclaration* getCurrentThis() const;
 
 	std::vector<MagicVariableDeclaration const*> getMagicVariables() const;
+	/// Returns a vector of all magic variables, excluding "this".
 	std::vector<Declaration*> getDeclarations() const;
 
 private:
-	MagicVariableDeclaration* getCurrentThis() const;
 	std::vector<std::shared_ptr<MagicVariableDeclaration>> m_magicVariables;
 	ContractDefinition const* m_currentContract;
 	std::map<ContractDefinition const*, std::shared_ptr<MagicVariableDeclaration>> mutable m_thisPointer;
diff --git a/libsolidity/NameAndTypeResolver.cpp b/libsolidity/NameAndTypeResolver.cpp
index d473348b8..08deb66a0 100644
--- a/libsolidity/NameAndTypeResolver.cpp
+++ b/libsolidity/NameAndTypeResolver.cpp
@@ -38,9 +38,13 @@ NameAndTypeResolver::NameAndTypeResolver(std::vector<Declaration*> const& _globa
 		m_scopes[nullptr].registerDeclaration(*declaration);
 }
 
+void NameAndTypeResolver::registerDeclarations(SourceUnit& _sourceUnit)
+{
+	DeclarationRegistrationHelper registrar(m_scopes, _sourceUnit);
+}
+
 void NameAndTypeResolver::resolveNamesAndTypes(ContractDefinition& _contract)
 {
-	DeclarationRegistrationHelper registrar(m_scopes, _contract);
 	m_currentScope = &m_scopes[&_contract];
 	for (ASTPointer<StructDefinition> const& structDef: _contract.getDefinedStructs())
 		ReferencesResolver resolver(*structDef, *this, nullptr);
@@ -65,6 +69,12 @@ void NameAndTypeResolver::resolveNamesAndTypes(ContractDefinition& _contract)
 	m_currentScope = &m_scopes[nullptr];
 }
 
+void NameAndTypeResolver::updateDeclaration(Declaration& _declaration)
+{
+	m_scopes[nullptr].registerDeclaration(_declaration, true);
+	_declaration.setScope(nullptr);
+}
+
 Declaration* NameAndTypeResolver::resolveName(ASTString const& _name, Declaration const* _scope) const
 {
 	auto iterator = m_scopes.find(_scope);
diff --git a/libsolidity/NameAndTypeResolver.h b/libsolidity/NameAndTypeResolver.h
index 797eca605..816d8006f 100644
--- a/libsolidity/NameAndTypeResolver.h
+++ b/libsolidity/NameAndTypeResolver.h
@@ -42,7 +42,13 @@ class NameAndTypeResolver: private boost::noncopyable
 {
 public:
 	explicit NameAndTypeResolver(std::vector<Declaration*> const& _globals);
+	/// Registers all declarations found in the source unit.
+	void registerDeclarations(SourceUnit& _sourceUnit);
+	/// Resolves all names and types referenced from the given contract.
 	void resolveNamesAndTypes(ContractDefinition& _contract);
+	/// Updates the given global declaration (used for "this"). Not to be used with declarations
+	/// that create their own scope.
+	void updateDeclaration(Declaration& _declaration);
 
 	/// Resolves the given @a _name inside the scope @a _scope. If @a _scope is omitted,
 	/// the global scope is used (i.e. the one containing only the contract).
diff --git a/libsolidity/Scanner.cpp b/libsolidity/Scanner.cpp
index 2f5f8d37a..e155f550d 100644
--- a/libsolidity/Scanner.cpp
+++ b/libsolidity/Scanner.cpp
@@ -143,17 +143,28 @@ private:
 }; // end of LiteralScope class
 
 
-void Scanner::reset(CharStream const& _source)
+void Scanner::reset(CharStream const& _source, std::string const& _sourceName)
 {
 	m_source = _source;
+
+	shared_ptr<string> sourceName = make_shared<string>(_sourceName);
+	m_currentToken.location.sourceName = sourceName;
+	m_nextToken.location.sourceName = sourceName;
+	m_skippedComment.location.sourceName = sourceName;
+	m_nextSkippedComment.location.sourceName = sourceName;
+
+	reset();
+}
+
+void Scanner::reset()
+{
+	m_source.reset();
 	m_char = m_source.get();
 	skipWhitespace();
 	scanToken();
-
 	next();
 }
 
-
 bool Scanner::scanHexByte(char& o_scannedByte)
 {
 	char x = 0;
diff --git a/libsolidity/Scanner.h b/libsolidity/Scanner.h
index 49ac3651c..deb7df502 100644
--- a/libsolidity/Scanner.h
+++ b/libsolidity/Scanner.h
@@ -79,6 +79,8 @@ public:
 	char advanceAndGet(size_t _chars=1);
 	char rollback(size_t _amount);
 
+	void reset() { m_pos = 0; }
+
 	///@{
 	///@name Error printing helper functions
 	/// Functions that help pretty-printing parse errors
@@ -99,11 +101,12 @@ class Scanner
 	friend class LiteralScope;
 public:
 
-	Scanner() { reset(CharStream()); }
-	explicit Scanner(CharStream const& _source) { reset(_source); }
+	explicit Scanner(CharStream const& _source = CharStream(), std::string const& _sourceName = "") { reset(_source, _sourceName); }
 
-	/// Resets the scanner as if newly constructed with _input as input.
-	void reset(CharStream const& _source);
+	/// Resets the scanner as if newly constructed with _source and _sourceName as input.
+	void reset(CharStream const& _source, std::string const& _sourceName);
+	/// Resets scanner to the start of input.
+	void reset();
 
 	/// Returns the next token and advances input
 	Token::Value next();
diff --git a/test/solidityCompiler.cpp b/test/solidityCompiler.cpp
index 883cecf28..9862cba83 100644
--- a/test/solidityCompiler.cpp
+++ b/test/solidityCompiler.cpp
@@ -48,10 +48,11 @@ bytes compileContract(const string& _sourceCode)
 	Parser parser;
 	ASTPointer<SourceUnit> sourceUnit;
 	BOOST_REQUIRE_NO_THROW(sourceUnit = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
+	NameAndTypeResolver resolver({});
+	resolver.registerDeclarations(*sourceUnit);
 	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
 		{
-			NameAndTypeResolver resolver({});
 			BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
 
 			Compiler compiler;
diff --git a/test/solidityExpressionCompiler.cpp b/test/solidityExpressionCompiler.cpp
index b077e2620..cb22d5120 100644
--- a/test/solidityExpressionCompiler.cpp
+++ b/test/solidityExpressionCompiler.cpp
@@ -88,10 +88,11 @@ bytes compileFirstExpression(const string& _sourceCode, vector<vector<string>> _
 	Parser parser;
 	ASTPointer<SourceUnit> sourceUnit;
 	BOOST_REQUIRE_NO_THROW(sourceUnit = parser.parse(make_shared<Scanner>(CharStream(_sourceCode))));
+	NameAndTypeResolver resolver({});
+	resolver.registerDeclarations(*sourceUnit);
 	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
 		{
-			NameAndTypeResolver resolver({});
 			BOOST_REQUIRE_NO_THROW(resolver.resolveNamesAndTypes(*contract));
 			FirstExpressionExtractor extractor(*contract);
 			BOOST_REQUIRE(extractor.getExpression() != nullptr);
diff --git a/test/solidityNameAndTypeResolution.cpp b/test/solidityNameAndTypeResolution.cpp
index 219fa2599..74af19b8f 100644
--- a/test/solidityNameAndTypeResolution.cpp
+++ b/test/solidityNameAndTypeResolution.cpp
@@ -42,10 +42,11 @@ void parseTextAndResolveNames(std::string const& _source)
 {
 	Parser parser;
 	ASTPointer<SourceUnit> sourceUnit = parser.parse(std::make_shared<Scanner>(CharStream(_source)));
+	NameAndTypeResolver resolver({});
+	resolver.registerDeclarations(*sourceUnit);
 	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
 		{
-			NameAndTypeResolver resolver({});
 			resolver.resolveNamesAndTypes(*contract);
 		}
 }

From 04c8d8bdc08398089225c3e134df8ad533c887b8 Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Wed, 3 Dec 2014 18:52:28 +0100
Subject: [PATCH 4/6] Improved external interface for multi-source and
 multi-contract compilation.

---
 alethzero/MainWin.cpp                    |  2 +-
 libsolidity/BaseTypes.h                  |  7 ++-
 libsolidity/CompilerStack.cpp            | 12 +++++-
 libsolidity/CompilerStack.h              |  3 ++
 libsolidity/Exceptions.h                 |  1 -
 libsolidity/Parser.cpp                   | 11 ++++-
 libsolidity/Parser.h                     |  1 +
 libsolidity/Scanner.cpp                  | 10 +----
 libsolidity/Scanner.h                    |  3 ++
 libsolidity/SourceReferenceFormatter.cpp | 41 +++++++-----------
 libsolidity/SourceReferenceFormatter.h   |  4 +-
 libweb3jsonrpc/WebThreeStubServer.cpp    |  2 +-
 mix/ConstantCompilationModel.cpp         |  2 +-
 solc/main.cpp                            | 55 +++++++++++++++---------
 test/solidityExpressionCompiler.cpp      |  1 +
 15 files changed, 88 insertions(+), 67 deletions(-)

diff --git a/alethzero/MainWin.cpp b/alethzero/MainWin.cpp
index 4a32f66b2..4126fbf08 100644
--- a/alethzero/MainWin.cpp
+++ b/alethzero/MainWin.cpp
@@ -1625,7 +1625,7 @@ void Main::on_data_textChanged()
 			catch (dev::Exception const& exception)
 			{
 				ostringstream error;
-				solidity::SourceReferenceFormatter::printExceptionInformation(error, exception, "Error", compiler.getScanner());
+				solidity::SourceReferenceFormatter::printExceptionInformation(error, exception, "Error", compiler);
 				solidity = "<h4>Solidity</h4><pre>" + QString::fromStdString(error.str()).toHtmlEscaped() + "</pre>";
 			}
 			catch (...)
diff --git a/libsolidity/BaseTypes.h b/libsolidity/BaseTypes.h
index 627aa7dfd..a8fd77c86 100644
--- a/libsolidity/BaseTypes.h
+++ b/libsolidity/BaseTypes.h
@@ -37,14 +37,13 @@ namespace solidity
  */
 struct Location
 {
-	Location(int _start, int _end): start(_start), end(_end) { }
+	Location(int _start, int _end, std::shared_ptr<std::string const> _sourceName):
+		start(_start), end(_end), sourceName(_sourceName) { }
 	Location(): start(-1), end(-1) { }
 
-	bool IsValid() const { return !!sourceName && start >= 0 && end >= start; }
-
-	std::shared_ptr<std::string> sourceName;
 	int start;
 	int end;
+	std::shared_ptr<std::string const> sourceName;
 };
 
 /// Stream output for Location (used e.g. in boost exceptions).
diff --git a/libsolidity/CompilerStack.cpp b/libsolidity/CompilerStack.cpp
index 49ac3b64c..198ded090 100644
--- a/libsolidity/CompilerStack.cpp
+++ b/libsolidity/CompilerStack.cpp
@@ -81,10 +81,20 @@ void CompilerStack::parse(string const& _sourceCode)
 	parse();
 }
 
-void CompilerStack::compile(bool _optimize)
+vector<string> CompilerStack::getContractNames()
 {
 	if (!m_parseSuccessful)
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
+	vector<string> contractNames;
+	for (auto const& contract: m_contracts)
+		contractNames.push_back(contract.first);
+	return contractNames;
+}
+
+void CompilerStack::compile(bool _optimize)
+{
+	if (!m_parseSuccessful)
+		parse();
 	for (Source const* source: m_sourceOrder)
 		for (ASTPointer<ASTNode> const& node: source->ast->getNodes())
 			if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
diff --git a/libsolidity/CompilerStack.h b/libsolidity/CompilerStack.h
index 0520f2b1b..a5b8ec41e 100644
--- a/libsolidity/CompilerStack.h
+++ b/libsolidity/CompilerStack.h
@@ -54,6 +54,9 @@ public:
 	void parse();
 	/// Sets the given source code as the only source unit and parses it.
 	void parse(std::string const& _sourceCode);
+	/// Returns a list of the contract names in the sources.
+	std::vector<std::string> getContractNames();
+
 	/// Compiles the source units that were prevously added and parsed.
 	void compile(bool _optimize = false);
 	/// Parses and compiles the given source code.
diff --git a/libsolidity/Exceptions.h b/libsolidity/Exceptions.h
index 1903c1dc2..ffd8a72d4 100644
--- a/libsolidity/Exceptions.h
+++ b/libsolidity/Exceptions.h
@@ -37,7 +37,6 @@ struct DeclarationError: virtual Exception {};
 struct CompilerError: virtual Exception {};
 struct InternalCompilerError: virtual Exception {};
 
-typedef boost::error_info<struct tag_sourcePosition, int> errinfo_sourcePosition;
 typedef boost::error_info<struct tag_sourceLocation, Location> errinfo_sourceLocation;
 
 }
diff --git a/libsolidity/Parser.cpp b/libsolidity/Parser.cpp
index c385dd8d1..ddab489b6 100644
--- a/libsolidity/Parser.cpp
+++ b/libsolidity/Parser.cpp
@@ -39,7 +39,8 @@ namespace solidity
 class Parser::ASTNodeFactory
 {
 public:
-	ASTNodeFactory(Parser const& _parser): m_parser(_parser), m_location(_parser.getPosition(), -1) {}
+	ASTNodeFactory(Parser const& _parser):
+		m_parser(_parser), m_location(_parser.getPosition(), -1, _parser.getSourceName()) {}
 
 	void markEndPosition() { m_location.end = m_parser.getEndPosition(); }
 	void setLocationEmpty() { m_location.end = m_location.start; }
@@ -81,6 +82,11 @@ ASTPointer<SourceUnit> Parser::parse(shared_ptr<Scanner> const& _scanner)
 	return nodeFactory.createNode<SourceUnit>(nodes);
 }
 
+std::shared_ptr<const string> const& Parser::getSourceName() const
+{
+	return m_scanner->getSourceName();
+}
+
 int Parser::getPosition() const
 {
 	return m_scanner->getCurrentLocation().start;
@@ -579,7 +585,8 @@ ASTPointer<ASTString> Parser::getLiteralAndAdvance()
 
 ParserError Parser::createParserError(string const& _description) const
 {
-	return ParserError() << errinfo_sourcePosition(getPosition()) << errinfo_comment(_description);
+	return ParserError() << errinfo_sourceLocation(Location(getPosition(), getPosition(), getSourceName()))
+						 << errinfo_comment(_description);
 }
 
 
diff --git a/libsolidity/Parser.h b/libsolidity/Parser.h
index 98a337b29..52a374e03 100644
--- a/libsolidity/Parser.h
+++ b/libsolidity/Parser.h
@@ -35,6 +35,7 @@ class Parser
 {
 public:
 	ASTPointer<SourceUnit> parse(std::shared_ptr<Scanner> const& _scanner);
+	std::shared_ptr<std::string const> const& getSourceName() const;
 
 private:
 	class ASTNodeFactory;
diff --git a/libsolidity/Scanner.cpp b/libsolidity/Scanner.cpp
index e155f550d..08bf744d4 100644
--- a/libsolidity/Scanner.cpp
+++ b/libsolidity/Scanner.cpp
@@ -143,16 +143,10 @@ private:
 }; // end of LiteralScope class
 
 
-void Scanner::reset(CharStream const& _source, std::string const& _sourceName)
+void Scanner::reset(CharStream const& _source, string const& _sourceName)
 {
 	m_source = _source;
-
-	shared_ptr<string> sourceName = make_shared<string>(_sourceName);
-	m_currentToken.location.sourceName = sourceName;
-	m_nextToken.location.sourceName = sourceName;
-	m_skippedComment.location.sourceName = sourceName;
-	m_nextSkippedComment.location.sourceName = sourceName;
-
+	m_sourceName = make_shared<string const>(_sourceName);
 	reset();
 }
 
diff --git a/libsolidity/Scanner.h b/libsolidity/Scanner.h
index deb7df502..18b1f5d3a 100644
--- a/libsolidity/Scanner.h
+++ b/libsolidity/Scanner.h
@@ -142,6 +142,8 @@ public:
 	std::string const& peekLiteral() const { return m_nextToken.literal; }
 	///@}
 
+	std::shared_ptr<std::string const> const& getSourceName() const { return m_sourceName; }
+
 	///@{
 	///@name Error printing helper functions
 	/// Functions that help pretty-printing parse errors
@@ -206,6 +208,7 @@ private:
 	TokenDesc m_nextToken;     // desc for next token (one token look-ahead)
 
 	CharStream m_source;
+	std::shared_ptr<std::string const> m_sourceName;
 
 	/// one character look-ahead, equals 0 at end of input
 	char m_char;
diff --git a/libsolidity/SourceReferenceFormatter.cpp b/libsolidity/SourceReferenceFormatter.cpp
index d3f2152a6..1a7d12a95 100644
--- a/libsolidity/SourceReferenceFormatter.cpp
+++ b/libsolidity/SourceReferenceFormatter.cpp
@@ -21,6 +21,7 @@
  */
 
 #include <libsolidity/SourceReferenceFormatter.h>
+#include <libsolidity/CompilerStack.h>
 #include <libsolidity/Scanner.h>
 #include <libsolidity/Exceptions.h>
 
@@ -38,7 +39,6 @@ void SourceReferenceFormatter::printSourceLocation(ostream& _stream,
 	int startLine;
 	int startColumn;
 	tie(startLine, startColumn) = _scanner.translatePositionToLineColumn(_location.start);
-	_stream << "starting at line " << (startLine + 1) << ", column " << (startColumn + 1) << "\n";
 	int endLine;
 	int endColumn;
 	tie(endLine, endColumn) = _scanner.translatePositionToLineColumn(_location.end);
@@ -58,37 +58,28 @@ void SourceReferenceFormatter::printSourceLocation(ostream& _stream,
 				<< "Spanning multiple lines.\n";
 }
 
-void SourceReferenceFormatter::printSourcePosition(ostream& _stream,
-												   int _position,
-												   const Scanner& _scanner)
-{
-	int line;
-	int column;
-	tie(line, column) = _scanner.translatePositionToLineColumn(_position);
-	_stream << "at line " << (line + 1) << ", column " << (column + 1) << endl
-			<< _scanner.getLineAtPosition(_position) << endl
-			<< string(column, ' ') << "^" << endl;
-}
-
 void SourceReferenceFormatter::printExceptionInformation(ostream& _stream,
 														 Exception const& _exception,
 														 string const& _name,
-														 Scanner const& _scanner)
+														 CompilerStack& _compiler)
 {
-	_stream << _name;
-	if (string const* description = boost::get_error_info<errinfo_comment>(_exception))
-		_stream << ": " << *description;
+	Location const* location = boost::get_error_info<errinfo_sourceLocation>(_exception);
+	Scanner const* scanner;
 
-	if (int const* position = boost::get_error_info<errinfo_sourcePosition>(_exception))
+	if (location)
 	{
-		_stream << " ";
-		printSourcePosition(_stream, *position, _scanner);
-	}
-	if (Location const* location = boost::get_error_info<errinfo_sourceLocation>(_exception))
-	{
-		_stream << " ";
-		printSourceLocation(_stream, *location, _scanner);
+		scanner = &_compiler.getScanner(*location->sourceName);
+		int startLine;
+		int startColumn;
+		tie(startLine, startColumn) = scanner->translatePositionToLineColumn(location->start);
+		_stream << *location->sourceName << ":" << (startLine + 1) << ":" << (startColumn + 1) << ": ";
 	}
+	_stream << _name;
+	if (string const* description = boost::get_error_info<errinfo_comment>(_exception))
+		_stream << ": " << *description << endl;
+
+	if (location)
+		printSourceLocation(_stream, *location, *scanner);
 }
 
 }
diff --git a/libsolidity/SourceReferenceFormatter.h b/libsolidity/SourceReferenceFormatter.h
index 4736066fd..9b5567045 100644
--- a/libsolidity/SourceReferenceFormatter.h
+++ b/libsolidity/SourceReferenceFormatter.h
@@ -34,14 +34,14 @@ namespace solidity
 {
 
 class Scanner; // forward
+class CompilerStack; // forward
 
 struct SourceReferenceFormatter
 {
 public:
 	static void printSourceLocation(std::ostream& _stream, Location const& _location, Scanner const& _scanner);
-	static void printSourcePosition(std::ostream& _stream, int _position, Scanner const& _scanner);
 	static void printExceptionInformation(std::ostream& _stream, Exception const& _exception,
-										  std::string const& _name, Scanner const& _scanner);
+										  std::string const& _name, CompilerStack& _compiler);
 };
 
 }
diff --git a/libweb3jsonrpc/WebThreeStubServer.cpp b/libweb3jsonrpc/WebThreeStubServer.cpp
index 7607b7a95..84a0ae42a 100644
--- a/libweb3jsonrpc/WebThreeStubServer.cpp
+++ b/libweb3jsonrpc/WebThreeStubServer.cpp
@@ -510,7 +510,7 @@ std::string WebThreeStubServer::eth_solidity(std::string const& _code)
 	catch (dev::Exception const& exception)
 	{
 		ostringstream error;
-		solidity::SourceReferenceFormatter::printExceptionInformation(error, exception, "Error", compiler.getScanner());
+		solidity::SourceReferenceFormatter::printExceptionInformation(error, exception, "Error", compiler);
 		cwarn << "Solidity compilation error: " << error.str();
 	}
 	catch (...)
diff --git a/mix/ConstantCompilationModel.cpp b/mix/ConstantCompilationModel.cpp
index e06734f59..ea12a267c 100644
--- a/mix/ConstantCompilationModel.cpp
+++ b/mix/ConstantCompilationModel.cpp
@@ -46,7 +46,7 @@ CompilerResult ConstantCompilationModel::compile(QString _code)
 	catch (dev::Exception const& _exception)
 	{
 		ostringstream error;
-		solidity::SourceReferenceFormatter::printExceptionInformation(error, _exception, "Error", compiler.getScanner());
+		solidity::SourceReferenceFormatter::printExceptionInformation(error, _exception, "Error", compiler);
 		res.success = false;
 		res.comment = QString::fromStdString(error.str()).toHtmlEscaped();
 		res.hexCode = "";
diff --git a/solc/main.cpp b/solc/main.cpp
index 76d8ef6b7..3284be74a 100644
--- a/solc/main.cpp
+++ b/solc/main.cpp
@@ -59,7 +59,7 @@ void version()
 
 int main(int argc, char** argv)
 {
-	string infile;
+	vector<string> infiles;
 	bool optimize = false;
 	for (int i = 1; i < argc; ++i)
 	{
@@ -71,49 +71,52 @@ int main(int argc, char** argv)
 		else if (arg == "-V" || arg == "--version")
 			version();
 		else
-			infile = argv[i];
+			infiles.push_back(argv[i]);
 	}
-	string sourceCode;
-	if (infile.empty())
+	map<string, string> sourceCodes;
+	if (infiles.empty())
 	{
 		string s;
 		while (!cin.eof())
 		{
 			getline(cin, s);
-			sourceCode.append(s);
+			sourceCodes["<stdin>"].append(s);
 		}
 	}
 	else
-		sourceCode = asString(dev::contents(infile));
+		for (string const& infile: infiles)
+			sourceCodes[infile] = asString(dev::contents(infile));
 
 	CompilerStack compiler;
 	try
 	{
-		compiler.compile(sourceCode, optimize);
+		for (auto const& sourceCode: sourceCodes)
+			compiler.addSource(sourceCode.first, sourceCode.second);
+		compiler.compile(optimize);
 	}
 	catch (ParserError const& exception)
 	{
-		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Parser error", compiler.getScanner());
+		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Parser error", compiler);
 		return -1;
 	}
 	catch (DeclarationError const& exception)
 	{
-		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Declaration error", compiler.getScanner());
+		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Declaration error", compiler);
 		return -1;
 	}
 	catch (TypeError const& exception)
 	{
-		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Type error", compiler.getScanner());
+		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Type error", compiler);
 		return -1;
 	}
 	catch (CompilerError const& exception)
 	{
-		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Compiler error", compiler.getScanner());
+		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Compiler error", compiler);
 		return -1;
 	}
 	catch (InternalCompilerError const& exception)
 	{
-		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Internal compiler error", compiler.getScanner());
+		SourceReferenceFormatter::printExceptionInformation(cerr, exception, "Internal compiler error", compiler);
 		return -1;
 	}
 	catch (Exception const& exception)
@@ -127,15 +130,25 @@ int main(int argc, char** argv)
 		return -1;
 	}
 
-	cout << "Syntax tree for the source unit:" << endl;
-	ASTPrinter printer(compiler.getAST(), sourceCode);
-	printer.print(cout);
-	cout << "EVM assembly:" << endl;
-	compiler.streamAssembly(cout);
-	cout << "Opcodes:" << endl;
-	cout << eth::disassemble(compiler.getBytecode()) << endl;
-	cout << "Binary: " << toHex(compiler.getBytecode()) << endl;
-	cout << "Interface specification: " << compiler.getInterface() << endl;
+	cout << "Syntax trees:" << endl << endl;
+	for (auto const& sourceCode: sourceCodes)
+	{
+		cout << endl << "======= " << sourceCode.first << " =======" << endl;
+		ASTPrinter printer(compiler.getAST(sourceCode.first), sourceCode.second);
+		printer.print(cout);
+	}
+	vector<string> contracts = compiler.getContractNames();
+	cout << endl << "Contracts:" << endl;
+	for (string const& contract: contracts)
+	{
+		cout << endl << "======= " << contract << " =======" << endl
+			 << "EVM assembly:" << endl;
+		compiler.streamAssembly(cout, contract);
+		cout << "Opcodes:" << endl
+			 << eth::disassemble(compiler.getBytecode(contract)) << endl
+			 << "Binary: " << toHex(compiler.getBytecode(contract)) << endl
+			 << "Interface specification: " << compiler.getInterface(contract) << endl;
+	}
 
 	return 0;
 }
diff --git a/test/solidityExpressionCompiler.cpp b/test/solidityExpressionCompiler.cpp
index cb22d5120..486b46ebb 100644
--- a/test/solidityExpressionCompiler.cpp
+++ b/test/solidityExpressionCompiler.cpp
@@ -113,6 +113,7 @@ bytes compileFirstExpression(const string& _sourceCode, vector<vector<string>> _
 			return instructions;
 		}
 	BOOST_FAIL("No contract found in source.");
+	return bytes();
 }
 
 } // end anonymous namespace

From dcce76392b0c3023729d43ae231c53e99a98ae2d Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Fri, 5 Dec 2014 15:35:05 +0100
Subject: [PATCH 5/6] Renamed url to identifier and added some comments.

---
 libsolidity/AST.h                   | 10 ++++++----
 libsolidity/ASTPrinter.cpp          |  2 +-
 libsolidity/CompilerStack.cpp       |  6 +++---
 libsolidity/CompilerStack.h         |  2 +-
 libsolidity/NameAndTypeResolver.cpp |  1 +
 5 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/libsolidity/AST.h b/libsolidity/AST.h
index d2fb15a45..10616022b 100644
--- a/libsolidity/AST.h
+++ b/libsolidity/AST.h
@@ -98,19 +98,21 @@ private:
 
 /**
  * Import directive for referencing other files / source objects.
+ * Example: import "abc.sol"
+ * Source objects are identified by a string which can be a file name but does not have to be.
  */
 class ImportDirective: public ASTNode
 {
 public:
-	ImportDirective(Location const& _location, ASTPointer<ASTString> const& _url):
-		ASTNode(_location), m_url(_url) {}
+	ImportDirective(Location const& _location, ASTPointer<ASTString> const& _identifier):
+		ASTNode(_location), m_identifier(_identifier) {}
 
 	virtual void accept(ASTVisitor& _visitor) override;
 
-	ASTString const& getURL() const { return *m_url; }
+	ASTString const& getIdentifier() const { return *m_identifier; }
 
 private:
-	ASTPointer<ASTString> m_url;
+	ASTPointer<ASTString> m_identifier;
 };
 
 /**
diff --git a/libsolidity/ASTPrinter.cpp b/libsolidity/ASTPrinter.cpp
index c62378fd3..3d09fd9af 100644
--- a/libsolidity/ASTPrinter.cpp
+++ b/libsolidity/ASTPrinter.cpp
@@ -45,7 +45,7 @@ void ASTPrinter::print(ostream& _stream)
 
 bool ASTPrinter::visit(ImportDirective& _node)
 {
-	writeLine("ImportDirective \"" + _node.getURL() + "\"");
+	writeLine("ImportDirective \"" + _node.getIdentifier() + "\"");
 	printSourcePart(_node);
 	return goDeeper();
 }
diff --git a/libsolidity/CompilerStack.cpp b/libsolidity/CompilerStack.cpp
index 621723848..20b0b3e57 100644
--- a/libsolidity/CompilerStack.cpp
+++ b/libsolidity/CompilerStack.cpp
@@ -201,12 +201,12 @@ void CompilerStack::resolveImports()
 		for (ASTPointer<ASTNode> const& node: _source->ast->getNodes())
 			if (ImportDirective const* import = dynamic_cast<ImportDirective*>(node.get()))
 			{
-				string const& url = import->getURL();
-				if (!m_sources.count(url))
+				string const& id = import->getIdentifier();
+				if (!m_sources.count(id))
 					BOOST_THROW_EXCEPTION(ParserError()
 										  << errinfo_sourceLocation(import->getLocation())
 										  << errinfo_comment("Source not found."));
-				toposort(&m_sources[url]);
+				toposort(&m_sources[id]);
 			}
 		sourceOrder.push_back(_source);
 	};
diff --git a/libsolidity/CompilerStack.h b/libsolidity/CompilerStack.h
index 34178841a..bedb4cc38 100644
--- a/libsolidity/CompilerStack.h
+++ b/libsolidity/CompilerStack.h
@@ -66,7 +66,7 @@ public:
 	/// Returns a list of the contract names in the sources.
 	std::vector<std::string> getContractNames();
 
-	/// Compiles the source units that were prevously added and parsed.
+	/// Compiles the source units that were previously added and parsed.
 	void compile(bool _optimize = false);
 	/// Parses and compiles the given source code.
 	/// @returns the compiled bytecode
diff --git a/libsolidity/NameAndTypeResolver.cpp b/libsolidity/NameAndTypeResolver.cpp
index 08deb66a0..3715df6ad 100644
--- a/libsolidity/NameAndTypeResolver.cpp
+++ b/libsolidity/NameAndTypeResolver.cpp
@@ -40,6 +40,7 @@ NameAndTypeResolver::NameAndTypeResolver(std::vector<Declaration*> const& _globa
 
 void NameAndTypeResolver::registerDeclarations(SourceUnit& _sourceUnit)
 {
+	// The helper registers all declarations in m_scopes as a side-effect of its construction.
 	DeclarationRegistrationHelper registrar(m_scopes, _sourceUnit);
 }
 

From ddb5111d3e959f4643fbc91751ec329e43b5db17 Mon Sep 17 00:00:00 2001
From: Christian <c@ethdev.com>
Date: Sun, 7 Dec 2014 09:46:21 +0100
Subject: [PATCH 6/6] Comments and braces.

---
 libsolidity/GlobalContext.h            | 3 ++-
 test/solidityNameAndTypeResolution.cpp | 2 --
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/libsolidity/GlobalContext.h b/libsolidity/GlobalContext.h
index fc3914d2a..ddbd049c2 100644
--- a/libsolidity/GlobalContext.h
+++ b/libsolidity/GlobalContext.h
@@ -49,8 +49,9 @@ public:
 	void setCurrentContract(ContractDefinition const& _contract);
 	MagicVariableDeclaration* getCurrentThis() const;
 
+	/// @returns all magic variables.
 	std::vector<MagicVariableDeclaration const*> getMagicVariables() const;
-	/// Returns a vector of all magic variables, excluding "this".
+	/// @returns a vector of all implicit global declarations excluding "this".
 	std::vector<Declaration*> getDeclarations() const;
 
 private:
diff --git a/test/solidityNameAndTypeResolution.cpp b/test/solidityNameAndTypeResolution.cpp
index 74af19b8f..783972296 100644
--- a/test/solidityNameAndTypeResolution.cpp
+++ b/test/solidityNameAndTypeResolution.cpp
@@ -46,9 +46,7 @@ void parseTextAndResolveNames(std::string const& _source)
 	resolver.registerDeclarations(*sourceUnit);
 	for (ASTPointer<ASTNode> const& node: sourceUnit->getNodes())
 		if (ContractDefinition* contract = dynamic_cast<ContractDefinition*>(node.get()))
-		{
 			resolver.resolveNamesAndTypes(*contract);
-		}
 }
 }