Merge pull request #893 from chriseth/sol_events

Events in Solidity

16 files changed, 245 insertions, 54 deletions

diff --git a/AST.cpp b/AST.cpp
index bc6be600..82d58d2a 100644
--- a/AST.cpp
+++ b/AST.cpp
@@ -271,6 +271,20 @@ void ModifierInvocation::checkTypeRequirements()
 			BOOST_THROW_EXCEPTION(createTypeError("Invalid type for argument in modifier invocation."));
 }
 
+void EventDefinition::checkTypeRequirements()
+{
+	int numIndexed = 0;
+	for (ASTPointer<VariableDeclaration> const& var: getParameters())
+	{
+		if (var->isIndexed())
+			numIndexed++;
+		if (!var->getType()->canLiveOutsideStorage())
+			BOOST_THROW_EXCEPTION(var->createTypeError("Type is required to live outside storage."));
+	}
+	if (numIndexed > 3)
+		BOOST_THROW_EXCEPTION(createTypeError("More than 3 indexed arguments for event."));
+}
+
 void Block::checkTypeRequirements()
 {
 	for (shared_ptr<Statement> const& statement: m_statements)
diff --git a/AST.h b/AST.h
index 6c207290..ab9815f6 100755
--- a/AST.h
+++ b/AST.h
@@ -202,13 +202,15 @@ public:
 					   std::vector<ASTPointer<StructDefinition>> const& _definedStructs,
 					   std::vector<ASTPointer<VariableDeclaration>> const& _stateVariables,
 					   std::vector<ASTPointer<FunctionDefinition>> const& _definedFunctions,
-					   std::vector<ASTPointer<ModifierDefinition>> const& _functionModifiers):
+					   std::vector<ASTPointer<ModifierDefinition>> const& _functionModifiers,
+					   std::vector<ASTPointer<EventDefinition>> const& _events):
 		Declaration(_location, _name), Documented(_documentation),
 		m_baseContracts(_baseContracts),
 		m_definedStructs(_definedStructs),
 		m_stateVariables(_stateVariables),
 		m_definedFunctions(_definedFunctions),
-		m_functionModifiers(_functionModifiers)
+		m_functionModifiers(_functionModifiers),
+		m_events(_events)
 	{}
 
 	virtual void accept(ASTVisitor& _visitor) override;
@@ -219,6 +221,7 @@ public:
 	std::vector<ASTPointer<VariableDeclaration>> const& getStateVariables() const { return m_stateVariables; }
 	std::vector<ASTPointer<ModifierDefinition>> const& getFunctionModifiers() const { return m_functionModifiers; }
 	std::vector<ASTPointer<FunctionDefinition>> const& getDefinedFunctions() const { return m_definedFunctions; }
+	std::vector<ASTPointer<EventDefinition>> const& getEvents() const { return m_events; }
 
 	virtual TypePointer getType(ContractDefinition const* m_currentContract) const override;
 
@@ -248,6 +251,7 @@ private:
 	std::vector<ASTPointer<VariableDeclaration>> m_stateVariables;
 	std::vector<ASTPointer<FunctionDefinition>> m_definedFunctions;
 	std::vector<ASTPointer<ModifierDefinition>> m_functionModifiers;
+	std::vector<ASTPointer<EventDefinition>> m_events;
 
 	std::vector<ContractDefinition const*> m_linearizedBaseContracts;
 	mutable std::unique_ptr<std::vector<std::pair<FixedHash<4>, FunctionTypePointer>>> m_interfaceFunctionList;
@@ -380,8 +384,10 @@ class VariableDeclaration: public Declaration
 {
 public:
 	VariableDeclaration(Location const& _location, ASTPointer<TypeName> const& _type,
-							ASTPointer<ASTString> const& _name, bool _isPublic, bool _isStateVar = false):
-	Declaration(_location, _name), m_typeName(_type), m_isPublic(_isPublic), m_isStateVariable(_isStateVar) {}
+						ASTPointer<ASTString> const& _name, bool _isPublic, bool _isStateVar = false,
+						bool _isIndexed = false):
+		Declaration(_location, _name), m_typeName(_type),
+		m_isPublic(_isPublic), m_isStateVariable(_isStateVar), m_isIndexed(_isIndexed) {}
 	virtual void accept(ASTVisitor& _visitor) override;
 	virtual void accept(ASTConstVisitor& _visitor) const override;
 
@@ -396,12 +402,13 @@ public:
 	bool isLocalVariable() const { return !!dynamic_cast<FunctionDefinition const*>(getScope()); }
 	bool isPublic() const { return m_isPublic; }
 	bool isStateVariable() const { return m_isStateVariable; }
-
+	bool isIndexed() const { return m_isIndexed; }
 
 private:
 	ASTPointer<TypeName> m_typeName;    ///< can be empty ("var")
 	bool m_isPublic;                    ///< Whether there is an accessor for it or not
 	bool m_isStateVariable;             ///< Whether or not this is a contract state variable
+	bool m_isIndexed;                   ///< Whether this is an indexed variable (used by events).
 
 	std::shared_ptr<Type const> m_type; ///< derived type, initially empty
 };
@@ -429,7 +436,6 @@ public:
 
 	virtual TypePointer getType(ContractDefinition const* = nullptr) const override;
 
-
 	void checkTypeRequirements();
 
 private:
@@ -461,6 +467,37 @@ private:
 };
 
 /**
+ * Definition of a (loggable) event.
+ */
+class EventDefinition: public Declaration, public Documented
+{
+public:
+	EventDefinition(Location const& _location,
+					ASTPointer<ASTString> const& _name,
+					ASTPointer<ASTString> const& _documentation,
+					ASTPointer<ParameterList> const& _parameters):
+		Declaration(_location, _name), Documented(_documentation), m_parameters(_parameters) {}
+
+	virtual void accept(ASTVisitor& _visitor) override;
+	virtual void accept(ASTConstVisitor& _visitor) const override;
+
+	std::vector<ASTPointer<VariableDeclaration>> const& getParameters() const { return m_parameters->getParameters(); }
+	ParameterList const& getParameterList() const { return *m_parameters; }
+	Block const& getBody() const { return *m_body; }
+
+	virtual TypePointer getType(ContractDefinition const* = nullptr) const override
+	{
+		return std::make_shared<FunctionType>(*this);
+	}
+
+	void checkTypeRequirements();
+
+private:
+	ASTPointer<ParameterList> m_parameters;
+	ASTPointer<Block> m_body;
+};
+
+/**
  * Pseudo AST node that is used as declaration for "this", "msg", "tx", "block" and the global
  * functions when such an identifier is encountered. Will never have a valid location in the source code.
  */
diff --git a/ASTForward.h b/ASTForward.h
index aa5cd49c..22015f26 100644
--- a/ASTForward.h
+++ b/ASTForward.h
@@ -45,6 +45,7 @@ class FunctionDefinition;
 class VariableDeclaration;
 class ModifierDefinition;
 class ModifierInvocation;
+class EventDefinition;
 class MagicVariableDeclaration;
 class TypeName;
 class ElementaryTypeName;
diff --git a/ASTPrinter.cpp b/ASTPrinter.cpp
index 05b24c63..949740e8 100644
--- a/ASTPrinter.cpp
+++ b/ASTPrinter.cpp
@@ -108,6 +108,13 @@ bool ASTPrinter::visit(ModifierInvocation const& _node)
 	return goDeeper();
 }
 
+bool ASTPrinter::visit(EventDefinition const& _node)
+{
+	writeLine("EventDefinition \"" + _node.getName() + "\"");
+	printSourcePart(_node);
+	return goDeeper();
+}
+
 bool ASTPrinter::visit(TypeName const& _node)
 {
 	writeLine("TypeName");
@@ -365,6 +372,11 @@ void ASTPrinter::endVisit(ModifierInvocation const&)
 	m_indentation--;
 }
 
+void ASTPrinter::endVisit(EventDefinition const&)
+{
+	m_indentation--;
+}
+
 void ASTPrinter::endVisit(TypeName const&)
 {
 	m_indentation--;
diff --git a/ASTPrinter.h b/ASTPrinter.h
index 77025b2d..ebc163e3 100644
--- a/ASTPrinter.h
+++ b/ASTPrinter.h
@@ -51,6 +51,7 @@ public:
 	bool visit(VariableDeclaration const& _node) override;
 	bool visit(ModifierDefinition const& _node) override;
 	bool visit(ModifierInvocation const& _node) override;
+	bool visit(EventDefinition const& _node) override;
 	bool visit(TypeName const& _node) override;
 	bool visit(ElementaryTypeName const& _node) override;
 	bool visit(UserDefinedTypeName const& _node) override;
@@ -89,6 +90,7 @@ public:
 	void endVisit(VariableDeclaration const&) override;
 	void endVisit(ModifierDefinition const&) override;
 	void endVisit(ModifierInvocation const&) override;
+	void endVisit(EventDefinition const&) override;
 	void endVisit(TypeName const&) override;
 	void endVisit(ElementaryTypeName const&) override;
 	void endVisit(UserDefinedTypeName const&) override;
diff --git a/ASTVisitor.h b/ASTVisitor.h
index 53fbd191..29490277 100644
--- a/ASTVisitor.h
+++ b/ASTVisitor.h
@@ -52,6 +52,7 @@ public:
 	virtual bool visit(VariableDeclaration&) { return true; }
 	virtual bool visit(ModifierDefinition&) { return true; }
 	virtual bool visit(ModifierInvocation&) { return true; }
+	virtual bool visit(EventDefinition&) { return true; }
 	virtual bool visit(TypeName&) { return true; }
 	virtual bool visit(ElementaryTypeName&) { return true; }
 	virtual bool visit(UserDefinedTypeName&) { return true; }
@@ -92,6 +93,7 @@ public:
 	virtual void endVisit(VariableDeclaration&) { }
 	virtual void endVisit(ModifierDefinition&) { }
 	virtual void endVisit(ModifierInvocation&) { }
+	virtual void endVisit(EventDefinition&) { }
 	virtual void endVisit(TypeName&) { }
 	virtual void endVisit(ElementaryTypeName&) { }
 	virtual void endVisit(UserDefinedTypeName&) { }
@@ -136,6 +138,7 @@ public:
 	virtual bool visit(VariableDeclaration const&) { return true; }
 	virtual bool visit(ModifierDefinition const&) { return true; }
 	virtual bool visit(ModifierInvocation const&) { return true; }
+	virtual bool visit(EventDefinition const&) { return true; }
 	virtual bool visit(TypeName const&) { return true; }
 	virtual bool visit(ElementaryTypeName const&) { return true; }
 	virtual bool visit(UserDefinedTypeName const&) { return true; }
@@ -176,6 +179,7 @@ public:
 	virtual void endVisit(VariableDeclaration const&) { }
 	virtual void endVisit(ModifierDefinition const&) { }
 	virtual void endVisit(ModifierInvocation const&) { }
+	virtual void endVisit(EventDefinition const&) { }
 	virtual void endVisit(TypeName const&) { }
 	virtual void endVisit(ElementaryTypeName const&) { }
 	virtual void endVisit(UserDefinedTypeName const&) { }
diff --git a/AST_accept.h b/AST_accept.h
index 481b150b..38108cd7 100644
--- a/AST_accept.h
+++ b/AST_accept.h
@@ -64,8 +64,9 @@ void ContractDefinition::accept(ASTVisitor& _visitor)
 		listAccept(m_baseContracts, _visitor);
 		listAccept(m_definedStructs, _visitor);
 		listAccept(m_stateVariables, _visitor);
-		listAccept(m_definedFunctions, _visitor);
+		listAccept(m_events, _visitor);
 		listAccept(m_functionModifiers, _visitor);
+		listAccept(m_definedFunctions, _visitor);
 	}
 	_visitor.endVisit(*this);
 }
@@ -77,8 +78,9 @@ void ContractDefinition::accept(ASTConstVisitor& _visitor) const
 		listAccept(m_baseContracts, _visitor);
 		listAccept(m_definedStructs, _visitor);
 		listAccept(m_stateVariables, _visitor);
-		listAccept(m_definedFunctions, _visitor);
+		listAccept(m_events, _visitor);
 		listAccept(m_functionModifiers, _visitor);
+		listAccept(m_definedFunctions, _visitor);
 	}
 	_visitor.endVisit(*this);
 }
@@ -219,6 +221,20 @@ void ModifierInvocation::accept(ASTConstVisitor& _visitor) const
 	_visitor.endVisit(*this);
 }
 
+void EventDefinition::accept(ASTVisitor& _visitor)
+{
+	if (_visitor.visit(*this))
+		m_parameters->accept(_visitor);
+	_visitor.endVisit(*this);
+}
+
+void EventDefinition::accept(ASTConstVisitor& _visitor) const
+{
+	if (_visitor.visit(*this))
+		m_parameters->accept(_visitor);
+	_visitor.endVisit(*this);
+}
+
 void TypeName::accept(ASTVisitor& _visitor)
 {
 	_visitor.visit(*this);
diff --git a/ExpressionCompiler.cpp b/ExpressionCompiler.cpp
index 5d44c86f..7d58ea2e 100644
--- a/ExpressionCompiler.cpp
+++ b/ExpressionCompiler.cpp
@@ -23,6 +23,7 @@
 #include <utility>
 #include <numeric>
 #include <libdevcore/Common.h>
+#include <libdevcrypto/SHA3.h>
 #include <libsolidity/AST.h>
 #include <libsolidity/ExpressionCompiler.h>
 #include <libsolidity/CompilerContext.h>
@@ -304,10 +305,7 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 			m_context << eth::Instruction::SUICIDE;
 			break;
 		case Location::SHA3:
-			arguments.front()->accept(*this);
-			appendTypeConversion(*arguments.front()->getType(), *function.getParameterTypes().front(), true);
-			// @todo move this once we actually use memory
-			CompilerUtils(m_context).storeInMemory(0);
+			appendExpressionCopyToMemory(*function.getParameterTypes().front(), *arguments.front());
 			m_context << u256(32) << u256(0) << eth::Instruction::SHA3;
 			break;
 		case Location::LOG0:
@@ -317,14 +315,41 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
 		case Location::LOG4:
 		{
 			unsigned logNumber = int(function.getLocation()) - int(Location::LOG0);
-			for (int arg = logNumber; arg >= 0; --arg)
+			for (unsigned arg = logNumber; arg > 0; --arg)
 			{
 				arguments[arg]->accept(*this);
 				appendTypeConversion(*arguments[arg]->getType(), *function.getParameterTypes()[arg], true);
 			}
-			// @todo move this once we actually use memory
-			CompilerUtils(m_context).storeInMemory(0);
-			m_context << u256(32) << u256(0) << eth::logInstruction(logNumber);
+			unsigned length = appendExpressionCopyToMemory(*function.getParameterTypes().front(),
+														   *arguments.front());
+			solAssert(length == 32, "Log data should be 32 bytes long (for now).");
+			m_context << u256(length) << u256(0) << eth::logInstruction(logNumber);
+			break;
+		}
+		case Location::EVENT:
+		{
+			_functionCall.getExpression().accept(*this);
+			auto const& event = dynamic_cast<EventDefinition const&>(function.getDeclaration());
+			// Copy all non-indexed arguments to memory (data)
+			unsigned numIndexed = 0;
+			unsigned memLength = 0;
+			for (unsigned arg = 0; arg < arguments.size(); ++arg)
+				if (!event.getParameters()[arg]->isIndexed())
+					memLength += appendExpressionCopyToMemory(*function.getParameterTypes()[arg],
+															  *arguments[arg], memLength);
+			// All indexed arguments go to the stack
+			for (unsigned arg = arguments.size(); arg > 0; --arg)
+				if (event.getParameters()[arg - 1]->isIndexed())
+				{
+					++numIndexed;
+					arguments[arg - 1]->accept(*this);
+					appendTypeConversion(*arguments[arg - 1]->getType(),
+										 *function.getParameterTypes()[arg - 1], true);
+				}
+			m_context << u256(h256::Arith(dev::sha3(function.getCanonicalSignature(event.getName()))));
+			++numIndexed;
+			solAssert(numIndexed <= 4, "Too many indexed arguments.");
+			m_context << u256(memLength) << u256(0) << eth::logInstruction(numIndexed);
 			break;
 		}
 		case Location::BLOCKHASH:
@@ -459,14 +484,13 @@ void ExpressionCompiler::endVisit(MemberAccess const& _memberAccess)
 bool ExpressionCompiler::visit(IndexAccess const& _indexAccess)
 {
 	_indexAccess.getBaseExpression().accept(*this);
-	_indexAccess.getIndexExpression().accept(*this);
-	appendTypeConversion(*_indexAccess.getIndexExpression().getType(),
-						 *dynamic_cast<MappingType const&>(*_indexAccess.getBaseExpression().getType()).getKeyType(),
-						 true);
+
+	TypePointer const& keyType = dynamic_cast<MappingType const&>(*_indexAccess.getBaseExpression().getType()).getKeyType();
+	unsigned length = appendExpressionCopyToMemory(*keyType, _indexAccess.getIndexExpression());
+	solAssert(length == 32, "Mapping key has to take 32 bytes in memory (for now).");
 	// @todo move this once we actually use memory
-	CompilerUtils(m_context).storeInMemory(0);
-	CompilerUtils(m_context).storeInMemory(32);
-	m_context << u256(64) << u256(0) << eth::Instruction::SHA3;
+	length += CompilerUtils(m_context).storeInMemory(length);
+	m_context << u256(length) << u256(0) << eth::Instruction::SHA3;
 
 	m_currentLValue = LValue(m_context, LValue::STORAGE, *_indexAccess.getType());
 	m_currentLValue.retrieveValueIfLValueNotRequested(_indexAccess);
@@ -495,6 +519,10 @@ void ExpressionCompiler::endVisit(Identifier const& _identifier)
 	{
 		// no-op
 	}
+	else if (dynamic_cast<EventDefinition const*>(declaration))
+	{
+		// no-op
+	}
 	else
 	{
 		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Identifier type not expected in expression context."));
@@ -791,22 +819,25 @@ unsigned ExpressionCompiler::appendArgumentCopyToMemory(TypePointers const& _typ
 {
 	unsigned length = 0;
 	for (unsigned i = 0; i < _arguments.size(); ++i)
-	{
-		_arguments[i]->accept(*this);
-		appendTypeConversion(*_arguments[i]->getType(), *_types[i], true);
-		unsigned const c_numBytes = _types[i]->getCalldataEncodedSize();
-		if (c_numBytes == 0 || c_numBytes > 32)
-			BOOST_THROW_EXCEPTION(CompilerError()
-								  << errinfo_sourceLocation(_arguments[i]->getLocation())
-								  << errinfo_comment("Type " + _types[i]->toString() + " not yet supported."));
-		bool const c_leftAligned = _types[i]->getCategory() == Type::Category::STRING;
-		bool const c_padToWords = true;
-		length += CompilerUtils(m_context).storeInMemory(_memoryOffset + length, c_numBytes,
-														 c_leftAligned, c_padToWords);
-	}
+		length += appendExpressionCopyToMemory(*_types[i], *_arguments[i], _memoryOffset + length);
 	return length;
 }
 
+unsigned ExpressionCompiler::appendExpressionCopyToMemory(Type const& _expectedType,
+														  Expression const& _expression, unsigned _memoryOffset)
+{
+	_expression.accept(*this);
+	appendTypeConversion(*_expression.getType(), _expectedType, true);
+	unsigned const c_numBytes = CompilerUtils::getPaddedSize(_expectedType.getCalldataEncodedSize());
+	if (c_numBytes == 0 || c_numBytes > 32)
+		BOOST_THROW_EXCEPTION(CompilerError()
+							  << errinfo_sourceLocation(_expression.getLocation())
+							  << errinfo_comment("Type " + _expectedType.toString() + " not yet supported."));
+	bool const c_leftAligned = _expectedType.getCategory() == Type::Category::STRING;
+	bool const c_padToWords = true;
+	return CompilerUtils(m_context).storeInMemory(_memoryOffset, c_numBytes, c_leftAligned, c_padToWords);
+}
+
 void ExpressionCompiler::appendStateVariableAccessor(VariableDeclaration const& _varDecl)
 {
 	m_currentLValue.fromStateVariable(_varDecl, _varDecl.getType());
diff --git a/ExpressionCompiler.h b/ExpressionCompiler.h
index 748cc6c6..caecbfe8 100644
--- a/ExpressionCompiler.h
+++ b/ExpressionCompiler.h
@@ -94,8 +94,13 @@ private:
 									bool bare = false);
 	/// Appends code that copies the given arguments to memory (with optional offset).
 	/// @returns the number of bytes copied to memory
-	unsigned appendArgumentCopyToMemory(TypePointers const& _functionType, std::vector<ASTPointer<Expression const>> const& _arguments,
+	unsigned appendArgumentCopyToMemory(TypePointers const& _types,
+										std::vector<ASTPointer<Expression const>> const& _arguments,
 										unsigned _memoryOffset = 0);
+	/// Appends code that evaluates a single expression and copies it to memory (with optional offset).
+	/// @returns the number of bytes copied to memory
+	unsigned appendExpressionCopyToMemory(Type const& _expectedType, Expression const& _expression,
+										  unsigned _memoryOffset = 0);
 
 	/// Appends code for a State Variable accessor function
 	void appendStateVariableAccessor(VariableDeclaration const& _varDecl);
diff --git a/NameAndTypeResolver.cpp b/NameAndTypeResolver.cpp
index 43201fe1..75df637c 100644
--- a/NameAndTypeResolver.cpp
+++ b/NameAndTypeResolver.cpp
@@ -60,6 +60,8 @@ void NameAndTypeResolver::resolveNamesAndTypes(ContractDefinition& _contract)
 		ReferencesResolver resolver(*structDef, *this, &_contract, nullptr);
 	for (ASTPointer<VariableDeclaration> const& variable: _contract.getStateVariables())
 		ReferencesResolver resolver(*variable, *this, &_contract, nullptr);
+	for (ASTPointer<EventDefinition> const& event: _contract.getEvents())
+		ReferencesResolver resolver(*event, *this, &_contract, nullptr);
 	for (ASTPointer<ModifierDefinition> const& modifier: _contract.getFunctionModifiers())
 	{
 		m_currentScope = &m_scopes[modifier.get()];
@@ -259,6 +261,12 @@ bool DeclarationRegistrationHelper::visit(VariableDeclaration& _declaration)
 	return true;
 }
 
+bool DeclarationRegistrationHelper::visit(EventDefinition& _event)
+{
+	registerDeclaration(_event, false);
+	return true;
+}
+
 void DeclarationRegistrationHelper::enterNewSubScope(Declaration const& _declaration)
 {
 	map<ASTNode const*, DeclarationContainer>::iterator iter;
diff --git a/NameAndTypeResolver.h b/NameAndTypeResolver.h
index ba327a59..4555491f 100644
--- a/NameAndTypeResolver.h
+++ b/NameAndTypeResolver.h
@@ -104,6 +104,7 @@ private:
 	void endVisit(ModifierDefinition& _modifier);
 	void endVisit(VariableDefinition& _variableDefinition);
 	bool visit(VariableDeclaration& _declaration);
+	bool visit(EventDefinition& _event);
 
 	void enterNewSubScope(Declaration const& _declaration);
 	void closeCurrentScope();
diff --git a/Parser.cpp b/Parser.cpp
index 5cfc8f46..48cca612 100644
--- a/Parser.cpp
+++ b/Parser.cpp
@@ -122,6 +122,7 @@ ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 	vector<ASTPointer<VariableDeclaration>> stateVariables;
 	vector<ASTPointer<FunctionDefinition>> functions;
 	vector<ASTPointer<ModifierDefinition>> modifiers;
+	vector<ASTPointer<EventDefinition>> events;
 	if (m_scanner->getCurrentToken() == Token::IS)
 		do
 		{
@@ -149,19 +150,23 @@ ASTPointer<ContractDefinition> Parser::parseContractDefinition()
 		else if (currentToken == Token::IDENTIFIER || currentToken == Token::MAPPING ||
 				 Token::isElementaryTypeName(currentToken))
 		{
-			bool const allowVar = false;
-			stateVariables.push_back(parseVariableDeclaration(allowVar, visibilityIsPublic, true));
+			VarDeclParserOptions options;
+			options.isPublic = visibilityIsPublic;
+			options.isStateVariable = true;
+			stateVariables.push_back(parseVariableDeclaration(options));
 			expectToken(Token::SEMICOLON);
 		}
 		else if (currentToken == Token::MODIFIER)
 			modifiers.push_back(parseModifierDefinition());
+		else if (currentToken == Token::EVENT)
+			events.push_back(parseEventDefinition());
 		else
 			BOOST_THROW_EXCEPTION(createParserError("Function, variable, struct or modifier declaration expected."));
 	}
 	nodeFactory.markEndPosition();
 	expectToken(Token::RBRACE);
 	return nodeFactory.createNode<ContractDefinition>(name, docString, baseContracts, structs,
-													  stateVariables, functions, modifiers);
+													  stateVariables, functions, modifiers, events);
 }
 
 ASTPointer<InheritanceSpecifier> Parser::parseInheritanceSpecifier()
@@ -236,8 +241,7 @@ ASTPointer<StructDefinition> Parser::parseStructDefinition()
 	expectToken(Token::LBRACE);
 	while (m_scanner->getCurrentToken() != Token::RBRACE)
 	{
-		bool const allowVar = false;
-		members.push_back(parseVariableDeclaration(allowVar));
+		members.push_back(parseVariableDeclaration());
 		expectToken(Token::SEMICOLON);
 	}
 	nodeFactory.markEndPosition();
@@ -245,12 +249,20 @@ ASTPointer<StructDefinition> Parser::parseStructDefinition()
 	return nodeFactory.createNode<StructDefinition>(name, members);
 }
 
-ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(bool _allowVar, bool _isPublic, bool _isStateVariable)
+ASTPointer<VariableDeclaration> Parser::parseVariableDeclaration(VarDeclParserOptions const& _options)
 {
 	ASTNodeFactory nodeFactory(*this);
-	ASTPointer<TypeName> type = parseTypeName(_allowVar);
+	ASTPointer<TypeName> type = parseTypeName(_options.allowVar);
+	bool isIndexed = false;
+	if (_options.allowIndexed && m_scanner->getCurrentToken() == Token::INDEXED)
+	{
+		isIndexed = true;
+		m_scanner->next();
+	}
 	nodeFactory.markEndPosition();
-	return nodeFactory.createNode<VariableDeclaration>(type, expectIdentifierToken(), _isPublic, _isStateVariable);
+	return nodeFactory.createNode<VariableDeclaration>(type, expectIdentifierToken(),
+													   _options.isPublic, _options.isStateVariable,
+													   isIndexed);
 }
 
 ASTPointer<ModifierDefinition> Parser::parseModifierDefinition()
@@ -280,6 +292,23 @@ ASTPointer<ModifierDefinition> Parser::parseModifierDefinition()
 	return nodeFactory.createNode<ModifierDefinition>(name, docstring, parameters, block);
 }
 
+ASTPointer<EventDefinition> Parser::parseEventDefinition()
+{
+	ASTNodeFactory nodeFactory(*this);
+	ASTPointer<ASTString> docstring;
+	if (m_scanner->getCurrentCommentLiteral() != "")
+		docstring = make_shared<ASTString>(m_scanner->getCurrentCommentLiteral());
+
+	expectToken(Token::EVENT);
+	ASTPointer<ASTString> name(expectIdentifierToken());
+	ASTPointer<ParameterList> parameters;
+	if (m_scanner->getCurrentToken() == Token::LPAREN)
+		parameters = parseParameterList(true, true);
+	nodeFactory.markEndPosition();
+	expectToken(Token::SEMICOLON);
+	return nodeFactory.createNode<EventDefinition>(name, docstring, parameters);
+}
+
 ASTPointer<ModifierInvocation> Parser::parseModifierInvocation()
 {
 	ASTNodeFactory nodeFactory(*this);
@@ -352,19 +381,20 @@ ASTPointer<Mapping> Parser::parseMapping()
 	return nodeFactory.createNode<Mapping>(keyType, valueType);
 }
 
-ASTPointer<ParameterList> Parser::parseParameterList(bool _allowEmpty)
+ASTPointer<ParameterList> Parser::parseParameterList(bool _allowEmpty, bool _allowIndexed)
 {
 	ASTNodeFactory nodeFactory(*this);
 	vector<ASTPointer<VariableDeclaration>> parameters;
+	VarDeclParserOptions options;
+	options.allowIndexed = _allowIndexed;
 	expectToken(Token::LPAREN);
 	if (!_allowEmpty || m_scanner->getCurrentToken() != Token::RPAREN)
 	{
-		bool const allowVar = false;
-		parameters.push_back(parseVariableDeclaration(allowVar));
+		parameters.push_back(parseVariableDeclaration(options));
 		while (m_scanner->getCurrentToken() != Token::RPAREN)
 		{
 			expectToken(Token::COMMA);
-			parameters.push_back(parseVariableDeclaration(allowVar));
+			parameters.push_back(parseVariableDeclaration(options));
 		}
 	}
 	nodeFactory.markEndPosition();
@@ -506,8 +536,9 @@ ASTPointer<Statement> Parser::parseVarDefOrExprStmt()
 ASTPointer<VariableDefinition> Parser::parseVariableDefinition()
 {
 	ASTNodeFactory nodeFactory(*this);
-	bool const allowVar = true;
-	ASTPointer<VariableDeclaration> variable = parseVariableDeclaration(allowVar);
+	VarDeclParserOptions options;
+	options.allowVar = true;
+	ASTPointer<VariableDeclaration> variable = parseVariableDeclaration(options);
 	ASTPointer<Expression> value;
 	if (m_scanner->getCurrentToken() == Token::ASSIGN)
 	{
diff --git a/Parser.h b/Parser.h
index d3bff67e..69478c81 100644
--- a/Parser.h
+++ b/Parser.h
@@ -45,6 +45,14 @@ private:
 	/// End position of the current token
 	int getEndPosition() const;
 
+	struct VarDeclParserOptions {
+		VarDeclParserOptions() {}
+		bool allowVar = false;
+		bool isPublic = false;
+		bool isStateVariable = false;
+		bool allowIndexed = false;
+	};
+
 	///@{
 	///@name Parsing functions for the AST nodes
 	ASTPointer<ImportDirective> parseImportDirective();
@@ -52,13 +60,14 @@ private:
 	ASTPointer<InheritanceSpecifier> parseInheritanceSpecifier();
 	ASTPointer<FunctionDefinition> parseFunctionDefinition(bool _isPublic, ASTString const* _contractName);
 	ASTPointer<StructDefinition> parseStructDefinition();
-	ASTPointer<VariableDeclaration> parseVariableDeclaration(bool _allowVar, bool _isPublic = false, bool _isStateVar = false);
+	ASTPointer<VariableDeclaration> parseVariableDeclaration(VarDeclParserOptions const& _options = VarDeclParserOptions());
 	ASTPointer<ModifierDefinition> parseModifierDefinition();
+	ASTPointer<EventDefinition> parseEventDefinition();
 	ASTPointer<ModifierInvocation> parseModifierInvocation();
 	ASTPointer<Identifier> parseIdentifier();
 	ASTPointer<TypeName> parseTypeName(bool _allowVar);
 	ASTPointer<Mapping> parseMapping();
-	ASTPointer<ParameterList> parseParameterList(bool _allowEmpty = true);
+	ASTPointer<ParameterList> parseParameterList(bool _allowEmpty = true, bool _allowIndexed = false);
 	ASTPointer<Block> parseBlock();
 	ASTPointer<Statement> parseStatement();
 	ASTPointer<IfStatement> parseIfStatement();
diff --git a/Token.h b/Token.h
index 55ec8e8e..ed42f90c 100644
--- a/Token.h
+++ b/Token.h
@@ -153,7 +153,9 @@ namespace solidity
 	K(DEFAULT, "default", 0)                                           \
 	K(DO, "do", 0)                                                     \
 	K(ELSE, "else", 0)                                                 \
+	K(EVENT, "event", 0)                                               \
 	K(IS, "is", 0)                                                     \
+	K(INDEXED, "indexed", 0)                                           \
 	K(FOR, "for", 0)                                                   \
 	K(FUNCTION, "function", 0)                                         \
 	K(IF, "if", 0)                                                     \
diff --git a/Types.cpp b/Types.cpp
index bebb4be1..0842e40b 100644
--- a/Types.cpp
+++ b/Types.cpp
@@ -633,6 +633,22 @@ FunctionType::FunctionType(VariableDeclaration const& _varDecl):
 	swap(retParamNames, m_returnParameterNames);
 }
 
+FunctionType::FunctionType(const EventDefinition& _event):
+	m_location(Location::EVENT), m_declaration(&_event)
+{
+	TypePointers params;
+	vector<string> paramNames;
+	params.reserve(_event.getParameters().size());
+	paramNames.reserve(_event.getParameters().size());
+	for (ASTPointer<VariableDeclaration> const& var: _event.getParameters())
+	{
+		paramNames.push_back(var->getName());
+		params.push_back(var->getType());
+	}
+	swap(params, m_parameterTypes);
+	swap(paramNames, m_parameterNames);
+}
+
 bool FunctionType::operator==(Type const& _other) const
 {
 	if (_other.getCategory() != getCategory())
diff --git a/Types.h b/Types.h
index 4b4d17d0..1f4d27a2 100644
--- a/Types.h
+++ b/Types.h
@@ -350,16 +350,18 @@ public:
 	/// INTERNAL: jump tag, EXTERNAL: contract address + function identifier,
 	/// BARE: contract address (non-abi contract call)
 	/// OTHERS: special virtual function, nothing on the stack
+	/// @todo This documentation is outdated, and Location should rather be named "Type"
 	enum class Location { INTERNAL, EXTERNAL, CREATION, SEND,
 						  SHA3, SUICIDE,
 						  ECRECOVER, SHA256, RIPEMD160,
-						  LOG0, LOG1, LOG2, LOG3, LOG4,
+						  LOG0, LOG1, LOG2, LOG3, LOG4, EVENT,
 						  SET_GAS, SET_VALUE, BLOCKHASH,
 						  BARE };
 
 	virtual Category getCategory() const override { return Category::FUNCTION; }
 	explicit FunctionType(FunctionDefinition const& _function, bool _isInternal = true);
 	explicit FunctionType(VariableDeclaration const& _varDecl);
+	explicit FunctionType(EventDefinition const& _event);
 	FunctionType(strings const& _parameterTypes, strings const& _returnParameterTypes,
 				 Location _location = Location::INTERNAL):
 		FunctionType(parseElementaryTypeVector(_parameterTypes), parseElementaryTypeVector(_returnParameterTypes),