Merge pull request #2510 from ethereum/develop

Version 0.4.12

16 files changed, 913 insertions, 387 deletions

diff --git a/libsolidity/interface/ABI.cpp b/libsolidity/interface/ABI.cpp
new file mode 100644
index 00000000..12f958fc
--- /dev/null
+++ b/libsolidity/interface/ABI.cpp
@@ -0,0 +1,116 @@
+/*
+        This file is part of solidity.
+
+        solidity is free software: you can redistribute it and/or modify
+        it under the terms of the GNU General Public License as published by
+        the Free Software Foundation, either version 3 of the License, or
+        (at your option) any later version.
+
+        solidity is distributed in the hope that it will be useful,
+        but WITHOUT ANY WARRANTY; without even the implied warranty of
+        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+        GNU General Public License for more details.
+
+        You should have received a copy of the GNU General Public License
+        along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Utilities to handle the Contract ABI (https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI)
+ */
+
+#include <libsolidity/interface/ABI.h>
+#include <boost/range/irange.hpp>
+#include <libsolidity/ast/AST.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+
+Json::Value ABI::generate(ContractDefinition const& _contractDef)
+{
+	Json::Value abi(Json::arrayValue);
+
+	for (auto it: _contractDef.interfaceFunctions())
+	{
+		auto externalFunctionType = it.second->interfaceFunctionType();
+		Json::Value method;
+		method["type"] = "function";
+		method["name"] = it.second->declaration().name();
+		method["constant"] = it.second->isConstant();
+		method["payable"] = it.second->isPayable();
+		method["inputs"] = formatTypeList(
+			externalFunctionType->parameterNames(),
+			externalFunctionType->parameterTypes(),
+			_contractDef.isLibrary()
+		);
+		method["outputs"] = formatTypeList(
+			externalFunctionType->returnParameterNames(),
+			externalFunctionType->returnParameterTypes(),
+			_contractDef.isLibrary()
+		);
+		abi.append(method);
+	}
+	if (_contractDef.constructor())
+	{
+		Json::Value method;
+		method["type"] = "constructor";
+		auto externalFunction = FunctionType(*_contractDef.constructor(), false).interfaceFunctionType();
+		solAssert(!!externalFunction, "");
+		method["payable"] = externalFunction->isPayable();
+		method["inputs"] = formatTypeList(
+			externalFunction->parameterNames(),
+			externalFunction->parameterTypes(),
+			_contractDef.isLibrary()
+		);
+		abi.append(method);
+	}
+	if (_contractDef.fallbackFunction())
+	{
+		auto externalFunctionType = FunctionType(*_contractDef.fallbackFunction(), false).interfaceFunctionType();
+		solAssert(!!externalFunctionType, "");
+		Json::Value method;
+		method["type"] = "fallback";
+		method["payable"] = externalFunctionType->isPayable();
+		abi.append(method);
+	}
+	for (auto const& it: _contractDef.interfaceEvents())
+	{
+		Json::Value event;
+		event["type"] = "event";
+		event["name"] = it->name();
+		event["anonymous"] = it->isAnonymous();
+		Json::Value params(Json::arrayValue);
+		for (auto const& p: it->parameters())
+		{
+			solAssert(!!p->annotation().type->interfaceType(false), "");
+			Json::Value input;
+			input["name"] = p->name();
+			input["type"] = p->annotation().type->interfaceType(false)->canonicalName(false);
+			input["indexed"] = p->isIndexed();
+			params.append(input);
+		}
+		event["inputs"] = params;
+		abi.append(event);
+	}
+
+	return abi;
+}
+
+Json::Value ABI::formatTypeList(
+	vector<string> const& _names,
+	vector<TypePointer> const& _types,
+	bool _forLibrary
+)
+{
+	Json::Value params(Json::arrayValue);
+	solAssert(_names.size() == _types.size(), "Names and types vector size does not match");
+	for (unsigned i = 0; i < _names.size(); ++i)
+	{
+		solAssert(_types[i], "");
+		Json::Value param;
+		param["name"] = _names[i];
+		param["type"] = _types[i]->canonicalName(_forLibrary);
+		params.append(param);
+	}
+	return params;
+}
diff --git a/libsolidity/interface/ABI.h b/libsolidity/interface/ABI.h
new file mode 100644
index 00000000..95b162a9
--- /dev/null
+++ b/libsolidity/interface/ABI.h
@@ -0,0 +1,56 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Utilities to handle the Contract ABI (https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI)
+ */
+
+#pragma once
+
+#include <string>
+#include <memory>
+#include <json/json.h>
+
+namespace dev
+{
+namespace solidity
+{
+
+// Forward declarations
+class ContractDefinition;
+class Type;
+using TypePointer = std::shared_ptr<Type const>;
+
+class ABI
+{
+public:
+	/// Get the ABI Interface of the contract
+	/// @param _contractDef The contract definition
+	/// @return             A JSONrepresentation of the contract's ABI Interface
+	static Json::Value generate(ContractDefinition const& _contractDef);
+private:
+	/// @returns a json value suitable for a list of types in function input or output
+	/// parameters or other places. If @a _forLibrary is true, complex types are referenced
+	/// by name, otherwise they are anonymously expanded.
+	static Json::Value formatTypeList(
+		std::vector<std::string> const& _names,
+		std::vector<TypePointer> const& _types,
+		bool _forLibrary
+	);
+};
+
+}
+}
diff --git a/libsolidity/interface/AssemblyStack.cpp b/libsolidity/interface/AssemblyStack.cpp
new file mode 100644
index 00000000..23524bb3
--- /dev/null
+++ b/libsolidity/interface/AssemblyStack.cpp
@@ -0,0 +1,119 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Full assembly stack that can support EVM-assembly and JULIA as input and EVM, EVM1.5 and
+ * eWasm as output.
+ */
+
+
+#include <libsolidity/interface/AssemblyStack.h>
+
+#include <libsolidity/parsing/Scanner.h>
+#include <libsolidity/inlineasm/AsmPrinter.h>
+#include <libsolidity/inlineasm/AsmParser.h>
+#include <libsolidity/inlineasm/AsmAnalysis.h>
+#include <libsolidity/inlineasm/AsmAnalysisInfo.h>
+#include <libsolidity/inlineasm/AsmCodeGen.h>
+
+#include <libevmasm/Assembly.h>
+
+#include <libjulia/backends/evm/EVMCodeTransform.h>
+#include <libjulia/backends/evm/EVMAssembly.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+
+
+Scanner const& AssemblyStack::scanner() const
+{
+	solAssert(m_scanner, "");
+	return *m_scanner;
+}
+
+bool AssemblyStack::parseAndAnalyze(std::string const& _sourceName, std::string const& _source)
+{
+	m_errors.clear();
+	m_analysisSuccessful = false;
+	m_scanner = make_shared<Scanner>(CharStream(_source), _sourceName);
+	m_parserResult = assembly::Parser(m_errorReporter, m_language == Language::JULIA).parse(m_scanner);
+	if (!m_errorReporter.errors().empty())
+		return false;
+	solAssert(m_parserResult, "");
+
+	return analyzeParsed();
+}
+
+bool AssemblyStack::analyze(assembly::Block const& _block, Scanner const* _scanner)
+{
+	m_errors.clear();
+	m_analysisSuccessful = false;
+	if (_scanner)
+		m_scanner = make_shared<Scanner>(*_scanner);
+	m_parserResult = make_shared<assembly::Block>(_block);
+
+	return analyzeParsed();
+}
+
+bool AssemblyStack::analyzeParsed()
+{
+	m_analysisInfo = make_shared<assembly::AsmAnalysisInfo>();
+	assembly::AsmAnalyzer analyzer(*m_analysisInfo, m_errorReporter, m_language == Language::JULIA);
+	m_analysisSuccessful = analyzer.analyze(*m_parserResult);
+	return m_analysisSuccessful;
+}
+
+MachineAssemblyObject AssemblyStack::assemble(Machine _machine) const
+{
+	solAssert(m_analysisSuccessful, "");
+	solAssert(m_parserResult, "");
+	solAssert(m_analysisInfo, "");
+
+	switch (_machine)
+	{
+	case Machine::EVM:
+	{
+		MachineAssemblyObject object;
+		eth::Assembly assembly;
+		assembly::CodeGenerator::assemble(*m_parserResult, *m_analysisInfo, assembly);
+		object.bytecode = make_shared<eth::LinkerObject>(assembly.assemble());
+		ostringstream tmp;
+		assembly.stream(tmp);
+		object.assembly = tmp.str();
+		return object;
+	}
+	case Machine::EVM15:
+	{
+		MachineAssemblyObject object;
+		julia::EVMAssembly assembly(true);
+		julia::CodeTransform(assembly, *m_analysisInfo, m_language == Language::JULIA, true)(*m_parserResult);
+		object.bytecode = make_shared<eth::LinkerObject>(assembly.finalize());
+		/// TOOD: fill out text representation
+		return object;
+	}
+	case Machine::eWasm:
+		solUnimplemented("eWasm backend is not yet implemented.");
+	}
+	// unreachable
+	return MachineAssemblyObject();
+}
+
+string AssemblyStack::print() const
+{
+	solAssert(m_parserResult, "");
+	return assembly::AsmPrinter(m_language == Language::JULIA)(*m_parserResult);
+}
diff --git a/libsolidity/interface/AssemblyStack.h b/libsolidity/interface/AssemblyStack.h
new file mode 100644
index 00000000..2ae596ed
--- /dev/null
+++ b/libsolidity/interface/AssemblyStack.h
@@ -0,0 +1,96 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * Full assembly stack that can support EVM-assembly and JULIA as input and EVM, EVM1.5 and
+ * eWasm as output.
+ */
+
+#pragma once
+
+#include <libsolidity/interface/ErrorReporter.h>
+#include <libevmasm/LinkerObject.h>
+
+#include <string>
+#include <memory>
+
+namespace dev
+{
+namespace solidity
+{
+class Scanner;
+namespace assembly
+{
+struct AsmAnalysisInfo;
+struct Block;
+}
+
+struct MachineAssemblyObject
+{
+	std::shared_ptr<eth::LinkerObject> bytecode;
+	std::string assembly;
+};
+
+/*
+ * Full assembly stack that can support EVM-assembly and JULIA as input and EVM, EVM1.5 and
+ * eWasm as output.
+ */
+class AssemblyStack
+{
+public:
+	enum class Language { JULIA, Assembly };
+	enum class Machine { EVM, EVM15, eWasm };
+
+	explicit AssemblyStack(Language _language = Language::Assembly):
+		m_language(_language), m_errorReporter(m_errors)
+	{}
+
+	/// @returns the scanner used during parsing
+	Scanner const& scanner() const;
+
+	/// Runs parsing and analysis steps, returns false if input cannot be assembled.
+	/// Multiple calls overwrite the previous state.
+	bool parseAndAnalyze(std::string const& _sourceName, std::string const& _source);
+
+	/// Runs analysis step on the supplied block, returns false if input cannot be assembled.
+	/// Multiple calls overwrite the previous state.
+	bool analyze(assembly::Block const& _block, Scanner const* _scanner = nullptr);
+
+	/// Run the assembly step (should only be called after parseAndAnalyze).
+	MachineAssemblyObject assemble(Machine _machine) const;
+
+	/// @returns the errors generated during parsing, analysis (and potentially assembly).
+	ErrorList const& errors() const { return m_errors; }
+
+	/// Pretty-print the input after having parsed it.
+	std::string print() const;
+
+private:
+	bool analyzeParsed();
+
+	Language m_language = Language::Assembly;
+
+	std::shared_ptr<Scanner> m_scanner;
+
+	bool m_analysisSuccessful = false;
+	std::shared_ptr<assembly::Block> m_parserResult;
+	std::shared_ptr<assembly::AsmAnalysisInfo> m_analysisInfo;
+	ErrorList m_errors;
+	ErrorReporter m_errorReporter;
+};
+
+}
+}
diff --git a/libsolidity/interface/CompilerStack.cpp b/libsolidity/interface/CompilerStack.cpp
index 9c9c9614..e2507821 100644
--- a/libsolidity/interface/CompilerStack.cpp
+++ b/libsolidity/interface/CompilerStack.cpp
@@ -37,9 +37,9 @@
 #include <libsolidity/analysis/PostTypeChecker.h>
 #include <libsolidity/analysis/SyntaxChecker.h>
 #include <libsolidity/codegen/Compiler.h>
-#include <libsolidity/interface/InterfaceHandler.h>
+#include <libsolidity/interface/ABI.h>
+#include <libsolidity/interface/Natspec.h>
 #include <libsolidity/interface/GasEstimator.h>
-#include <libsolidity/formal/Why3Translator.h>
 
 #include <libevmasm/Exceptions.h>
 
@@ -56,9 +56,6 @@ using namespace std;
 using namespace dev;
 using namespace dev::solidity;
 
-CompilerStack::CompilerStack(ReadFile::Callback const& _readFile):
-	m_readFile(_readFile) {}
-
 void CompilerStack::setRemappings(vector<string> const& _remappings)
 {
 	vector<Remapping> remappings;
@@ -87,6 +84,7 @@ void CompilerStack::reset(bool _keepSources)
 	}
 	else
 	{
+		m_stackState = Empty;
 		m_sources.clear();
 	}
 	m_optimize = false;
@@ -95,8 +93,7 @@ void CompilerStack::reset(bool _keepSources)
 	m_scopes.clear();
 	m_sourceOrder.clear();
 	m_contracts.clear();
-	m_errors.clear();
-	m_stackState = Empty;
+	m_errorReporter.clear();
 }
 
 bool CompilerStack::addSource(string const& _name, string const& _content, bool _isLibrary)
@@ -120,15 +117,11 @@ bool CompilerStack::parse()
 	//reset
 	if(m_stackState != SourcesSet)
 		return false;
-	m_errors.clear();
+	m_errorReporter.clear();
 	ASTNode::resetID();
 
 	if (SemVerVersion{string(VersionString)}.isPrerelease())
-	{
-		auto err = make_shared<Error>(Error::Type::Warning);
-		*err << errinfo_comment("This is a pre-release compiler version, please do not use it in production.");
-		m_errors.push_back(err);
-	}
+		m_errorReporter.warning("This is a pre-release compiler version, please do not use it in production.");
 
 	vector<string> sourcesToParse;
 	for (auto const& s: m_sources)
@@ -138,9 +131,9 @@ bool CompilerStack::parse()
 		string const& path = sourcesToParse[i];
 		Source& source = m_sources[path];
 		source.scanner->reset();
-		source.ast = Parser(m_errors).parse(source.scanner);
+		source.ast = Parser(m_errorReporter).parse(source.scanner);
 		if (!source.ast)
-			solAssert(!Error::containsOnlyWarnings(m_errors), "Parser returned null but did not report error.");
+			solAssert(!Error::containsOnlyWarnings(m_errorReporter.errors()), "Parser returned null but did not report error.");
 		else
 		{
 			source.ast->annotation().path = path;
@@ -153,7 +146,7 @@ bool CompilerStack::parse()
 			}
 		}
 	}
-	if (Error::containsOnlyWarnings(m_errors))
+	if (Error::containsOnlyWarnings(m_errorReporter.errors()))
 	{
 		m_stackState = ParsingSuccessful;
 		return true;
@@ -169,18 +162,18 @@ bool CompilerStack::analyze()
 	resolveImports();
 
 	bool noErrors = true;
-	SyntaxChecker syntaxChecker(m_errors);
+	SyntaxChecker syntaxChecker(m_errorReporter);
 	for (Source const* source: m_sourceOrder)
 		if (!syntaxChecker.checkSyntax(*source->ast))
 			noErrors = false;
 
-	DocStringAnalyser docStringAnalyser(m_errors);
+	DocStringAnalyser docStringAnalyser(m_errorReporter);
 	for (Source const* source: m_sourceOrder)
 		if (!docStringAnalyser.analyseDocStrings(*source->ast))
 			noErrors = false;
 
 	m_globalContext = make_shared<GlobalContext>();
-	NameAndTypeResolver resolver(m_globalContext->declarations(), m_scopes, m_errors);
+	NameAndTypeResolver resolver(m_globalContext->declarations(), m_scopes, m_errorReporter);
 	for (Source const* source: m_sourceOrder)
 		if (!resolver.registerDeclarations(*source->ast))
 			return false;
@@ -216,11 +209,11 @@ bool CompilerStack::analyze()
 			{
 				m_globalContext->setCurrentContract(*contract);
 				resolver.updateDeclaration(*m_globalContext->currentThis());
-				TypeChecker typeChecker(m_errors);
+				TypeChecker typeChecker(m_errorReporter);
 				if (typeChecker.checkTypeRequirements(*contract))
 				{
-					contract->setDevDocumentation(InterfaceHandler::devDocumentation(*contract));
-					contract->setUserDocumentation(InterfaceHandler::userDocumentation(*contract));
+					contract->setDevDocumentation(Natspec::devDocumentation(*contract));
+					contract->setUserDocumentation(Natspec::userDocumentation(*contract));
 				}
 				else
 					noErrors = false;
@@ -236,7 +229,7 @@ bool CompilerStack::analyze()
 
 	if (noErrors)
 	{
-		PostTypeChecker postTypeChecker(m_errors);
+		PostTypeChecker postTypeChecker(m_errorReporter);
 		for (Source const* source: m_sourceOrder)
 			if (!postTypeChecker.check(*source->ast))
 				noErrors = false;
@@ -244,7 +237,7 @@ bool CompilerStack::analyze()
 
 	if (noErrors)
 	{
-		StaticAnalyzer staticAnalyzer(m_errors);
+		StaticAnalyzer staticAnalyzer(m_errorReporter);
 		for (Source const* source: m_sourceOrder)
 			if (!staticAnalyzer.analyze(*source->ast))
 				noErrors = false;
@@ -322,20 +315,6 @@ void CompilerStack::link()
 	}
 }
 
-bool CompilerStack::prepareFormalAnalysis(ErrorList* _errors)
-{
-	if (!_errors)
-		_errors = &m_errors;
-	Why3Translator translator(*_errors);
-	for (Source const* source: m_sourceOrder)
-		if (!translator.process(*source->ast))
-			return false;
-
-	m_formalTranslation = translator.translation();
-
-	return true;
-}
-
 eth::AssemblyItems const* CompilerStack::assemblyItems(string const& _contractName) const
 {
 	Contract const& currentContract = contract(_contractName);
@@ -406,15 +385,6 @@ eth::LinkerObject const& CompilerStack::cloneObject(string const& _contractName)
 	return contract(_contractName).cloneObject;
 }
 
-dev::h256 CompilerStack::contractCodeHash(string const& _contractName) const
-{
-	auto const& obj = runtimeObject(_contractName);
-	if (obj.bytecode.empty() || !obj.linkReferences.empty())
-		return dev::h256();
-	else
-		return dev::keccak256(obj.bytecode);
-}
-
 Json::Value CompilerStack::streamAssembly(ostream& _outStream, string const& _contractName, StringMap _sourceCodes, bool _inJsonFormat) const
 {
 	Contract const& currentContract = contract(_contractName);
@@ -444,20 +414,31 @@ map<string, unsigned> CompilerStack::sourceIndices() const
 	return indices;
 }
 
-Json::Value const& CompilerStack::interface(string const& _contractName) const
+Json::Value const& CompilerStack::contractABI(string const& _contractName) const
 {
-	return metadata(_contractName, DocumentationType::ABIInterface);
+	return contractABI(contract(_contractName));
 }
 
-Json::Value const& CompilerStack::metadata(string const& _contractName, DocumentationType _type) const
+Json::Value const& CompilerStack::contractABI(Contract const& _contract) const
 {
 	if (m_stackState < AnalysisSuccessful)
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
 
-	return metadata(contract(_contractName), _type);
+	solAssert(_contract.contract, "");
+
+	// caches the result
+	if (!_contract.abi)
+		_contract.abi.reset(new Json::Value(ABI::generate(*_contract.contract)));
+
+	return *_contract.abi;
 }
 
-Json::Value const& CompilerStack::metadata(Contract const& _contract, DocumentationType _type) const
+Json::Value const& CompilerStack::natspec(string const& _contractName, DocumentationType _type) const
+{
+	return natspec(contract(_contractName), _type);
+}
+
+Json::Value const& CompilerStack::natspec(Contract const& _contract, DocumentationType _type) const
 {
 	if (m_stackState < AnalysisSuccessful)
 		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
@@ -474,40 +455,54 @@ Json::Value const& CompilerStack::metadata(Contract const& _contract, Documentat
 	case DocumentationType::NatspecDev:
 		doc = &_contract.devDocumentation;
 		break;
-	case DocumentationType::ABIInterface:
-		doc = &_contract.interface;
-		break;
 	default:
 		BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Illegal documentation type."));
 	}
 
 	// caches the result
 	if (!*doc)
-		doc->reset(new Json::Value(InterfaceHandler::documentation(*_contract.contract, _type)));
+		doc->reset(new Json::Value(Natspec::documentation(*_contract.contract, _type)));
 
 	return *(*doc);
 }
 
+Json::Value CompilerStack::methodIdentifiers(string const& _contractName) const
+{
+	Json::Value methodIdentifiers(Json::objectValue);
+	for (auto const& it: contractDefinition(_contractName).interfaceFunctions())
+		methodIdentifiers[it.second->externalSignature()] = toHex(it.first.ref());
+	return methodIdentifiers;
+}
+
 string const& CompilerStack::onChainMetadata(string const& _contractName) const
 {
 	if (m_stackState != CompilationSuccessful)
-		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Compilation was not successful."));
 
 	return contract(_contractName).onChainMetadata;
 }
 
 Scanner const& CompilerStack::scanner(string const& _sourceName) const
 {
+	if (m_stackState < SourcesSet)
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("No sources set."));
+
 	return *source(_sourceName).scanner;
 }
 
 SourceUnit const& CompilerStack::ast(string const& _sourceName) const
 {
+	if (m_stackState < ParsingSuccessful)
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Parsing was not successful."));
+
 	return *source(_sourceName).ast;
 }
 
 ContractDefinition const& CompilerStack::contractDefinition(string const& _contractName) const
 {
+	if (m_stackState != CompilationSuccessful)
+		BOOST_THROW_EXCEPTION(CompilerError() << errinfo_comment("Compilation was not successful."));
+
 	return *contract(_contractName).contract;
 }
 
@@ -564,11 +559,10 @@ StringMap CompilerStack::loadMissingSources(SourceUnit const& _ast, std::string
 				newSources[importPath] = result.contentsOrErrorMessage;
 			else
 			{
-				auto err = make_shared<Error>(Error::Type::ParserError);
-				*err <<
-					errinfo_sourceLocation(import->location()) <<
-					errinfo_comment("Source \"" + importPath + "\" not found: " + result.contentsOrErrorMessage);
-				m_errors.push_back(std::move(err));
+				m_errorReporter.parserError(
+					import->location(),
+					string("Source \"" + importPath + "\" not found: " + result.contentsOrErrorMessage)
+				);
 				continue;
 			}
 		}
@@ -734,11 +728,6 @@ void CompilerStack::compileContract(
 	}
 }
 
-std::string CompilerStack::defaultContractName() const
-{
-	return contract("").contract->name();
-}
-
 CompilerStack::Contract const& CompilerStack::contract(string const& _contractName) const
 {
 	if (m_contracts.empty())
@@ -821,9 +810,9 @@ string CompilerStack::createOnChainMetadata(Contract const& _contract) const
 	for (auto const& library: m_libraries)
 		meta["settings"]["libraries"][library.first] = "0x" + toHex(library.second.asBytes());
 
-	meta["output"]["abi"] = metadata(_contract, DocumentationType::ABIInterface);
-	meta["output"]["userdoc"] = metadata(_contract, DocumentationType::NatspecUser);
-	meta["output"]["devdoc"] = metadata(_contract, DocumentationType::NatspecDev);
+	meta["output"]["abi"] = contractABI(_contract);
+	meta["output"]["userdoc"] = natspec(_contract, DocumentationType::NatspecUser);
+	meta["output"]["devdoc"] = natspec(_contract, DocumentationType::NatspecDev);
 
 	return jsonCompactPrint(meta);
 }
diff --git a/libsolidity/interface/CompilerStack.h b/libsolidity/interface/CompilerStack.h
index c1d344ca..03a1b806 100644
--- a/libsolidity/interface/CompilerStack.h
+++ b/libsolidity/interface/CompilerStack.h
@@ -35,7 +35,7 @@
 #include <libdevcore/FixedHash.h>
 #include <libevmasm/SourceLocation.h>
 #include <libevmasm/LinkerObject.h>
-#include <libsolidity/interface/Exceptions.h>
+#include <libsolidity/interface/ErrorReporter.h>
 #include <libsolidity/interface/ReadFile.h>
 
 namespace dev
@@ -59,15 +59,14 @@ class FunctionDefinition;
 class SourceUnit;
 class Compiler;
 class GlobalContext;
-class InterfaceHandler;
+class Natspec;
 class Error;
 class DeclarationContainer;
 
 enum class DocumentationType: uint8_t
 {
 	NatspecUser = 1,
-	NatspecDev,
-	ABIInterface
+	NatspecDev
 };
 
 /**
@@ -78,10 +77,21 @@ enum class DocumentationType: uint8_t
 class CompilerStack: boost::noncopyable
 {
 public:
+	enum State {
+		Empty,
+		SourcesSet,
+		ParsingSuccessful,
+		AnalysisSuccessful,
+		CompilationSuccessful
+	};
+
 	/// Creates a new compiler stack.
 	/// @param _readFile callback to used to read files for import statements. Must return
 	/// and must not emit exceptions.
-	explicit CompilerStack(ReadFile::Callback const& _readFile = ReadFile::Callback());
+	explicit CompilerStack(ReadFile::Callback const& _readFile = ReadFile::Callback()):
+		m_readFile(_readFile),
+		m_errorList(),
+		m_errorReporter(m_errorList) {}
 
 	/// Sets path remappings in the format "context:prefix=target"
 	void setRemappings(std::vector<std::string> const& _remappings);
@@ -115,7 +125,6 @@ public:
 	bool parseAndAnalyze(std::string const& _sourceCode);
 	/// @returns a list of the contract names in the sources.
 	std::vector<std::string> contractNames() const;
-	std::string defaultContractName() const;
 
 	/// Compiles the source units that were previously added and parsed.
 	/// @returns false on error.
@@ -128,12 +137,6 @@ public:
 	/// @returns false on error.
 	bool compile(std::string const& _sourceCode, bool _optimize = false, unsigned _runs = 200);
 
-	/// Tries to translate all source files into a language suitable for formal analysis.
-	/// @param _errors list to store errors - defaults to the internal error list.
-	/// @returns false on error.
-	bool prepareFormalAnalysis(ErrorList* _errors = nullptr);
-	std::string const& formalTranslation() const { return m_formalTranslation; }
-
 	/// @returns the assembled object for a contract.
 	eth::LinkerObject const& object(std::string const& _contractName = "") const;
 	/// @returns the runtime object for the contract.
@@ -157,11 +160,6 @@ public:
 	/// @returns either the contract's name or a mixture of its name and source file, sanitized for filesystem use
 	std::string const filesystemFriendlyName(std::string const& _contractName) const;
 
-	/// @returns hash of the runtime bytecode for the contract, i.e. the code that is
-	/// returned by the constructor or the zero-h256 if the contract still needs to be linked or
-	/// does not have runtime code.
-	dev::h256 contractCodeHash(std::string const& _contractName = "") const;
-
 	/// Streams a verbose version of the assembly to @a _outStream.
 	/// @arg _sourceCodes is the map of input files to source code strings
 	/// @arg _inJsonFromat shows whether the out should be in Json format
@@ -173,14 +171,18 @@ public:
 	/// @returns a mapping assigning each source name its index inside the vector returned
 	/// by sourceNames().
 	std::map<std::string, unsigned> sourceIndices() const;
-	/// @returns a JSON representing the contract interface.
+	/// @returns a JSON representing the contract ABI.
 	/// Prerequisite: Successful call to parse or compile.
-	Json::Value const& interface(std::string const& _contractName = "") const;
+	Json::Value const& contractABI(std::string const& _contractName = "") const;
 	/// @returns a JSON representing the contract's documentation.
 	/// Prerequisite: Successful call to parse or compile.
 	/// @param type The type of the documentation to get.
 	/// Can be one of 4 types defined at @c DocumentationType
-	Json::Value const& metadata(std::string const& _contractName, DocumentationType _type) const;
+	Json::Value const& natspec(std::string const& _contractName, DocumentationType _type) const;
+
+	/// @returns a JSON representing a map of method identifiers (hashes) to function names.
+	Json::Value methodIdentifiers(std::string const& _contractName) const;
+
 	std::string const& onChainMetadata(std::string const& _contractName) const;
 	void useMetadataLiteralSources(bool _metadataLiteralSources) { m_metadataLiteralSources = _metadataLiteralSources; }
 
@@ -191,16 +193,6 @@ public:
 	Scanner const& scanner(std::string const& _sourceName = "") const;
 	/// @returns the parsed source unit with the supplied name.
 	SourceUnit const& ast(std::string const& _sourceName = "") const;
-	/// @returns the parsed contract with the supplied name. Throws an exception if the contract
-	/// does not exist.
-	ContractDefinition const& contractDefinition(std::string const& _contractName) const;
-
-	/// @returns the offset of the entry point of the given function into the list of assembly items
-	/// or zero if it is not found or does not exist.
-	size_t functionEntryPoint(
-		std::string const& _contractName,
-		FunctionDefinition const& _function
-	) const;
 
 	/// Helper function for logs printing. Do only use in error cases, it's quite expensive.
 	/// line and columns are numbered starting from 1 with following order:
@@ -208,7 +200,9 @@ public:
 	std::tuple<int, int, int, int> positionFromSourceLocation(SourceLocation const& _sourceLocation) const;
 
 	/// @returns the list of errors that occured during parsing and type checking.
-	ErrorList const& errors() const { return m_errors; }
+	ErrorList const& errors() { return m_errorReporter.errors(); }
+
+	State state() const { return m_stackState; }
 
 private:
 	/**
@@ -230,20 +224,12 @@ private:
 		eth::LinkerObject runtimeObject;
 		eth::LinkerObject cloneObject;
 		std::string onChainMetadata; ///< The metadata json that will be hashed into the chain.
-		mutable std::unique_ptr<Json::Value const> interface;
+		mutable std::unique_ptr<Json::Value const> abi;
 		mutable std::unique_ptr<Json::Value const> userDocumentation;
 		mutable std::unique_ptr<Json::Value const> devDocumentation;
 		mutable std::unique_ptr<std::string const> sourceMapping;
 		mutable std::unique_ptr<std::string const> runtimeSourceMapping;
 	};
-	enum State {
-		Empty,
-		SourcesSet,
-		ParsingSuccessful,
-		AnalysisSuccessful,
-		CompilationSuccessful
-	};
-
 	/// Loads the missing sources from @a _ast (named @a _path) using the callback
 	/// @a m_readFile and stores the absolute paths of all imports in the AST annotations.
 	/// @returns the newly loaded sources.
@@ -265,9 +251,21 @@ private:
 	Contract const& contract(std::string const& _contractName = "") const;
 	Source const& source(std::string const& _sourceName = "") const;
 
+	/// @returns the parsed contract with the supplied name. Throws an exception if the contract
+	/// does not exist.
+	ContractDefinition const& contractDefinition(std::string const& _contractName) const;
+
 	std::string createOnChainMetadata(Contract const& _contract) const;
 	std::string computeSourceMapping(eth::AssemblyItems const& _items) const;
-	Json::Value const& metadata(Contract const&, DocumentationType _type) const;
+	Json::Value const& contractABI(Contract const&) const;
+	Json::Value const& natspec(Contract const&, DocumentationType _type) const;
+
+	/// @returns the offset of the entry point of the given function into the list of assembly items
+	/// or zero if it is not found or does not exist.
+	size_t functionEntryPoint(
+		std::string const& _contractName,
+		FunctionDefinition const& _function
+	) const;
 
 	struct Remapping
 	{
@@ -288,8 +286,8 @@ private:
 	std::map<ASTNode const*, std::shared_ptr<DeclarationContainer>> m_scopes;
 	std::vector<Source const*> m_sourceOrder;
 	std::map<std::string const, Contract> m_contracts;
-	std::string m_formalTranslation;
-	ErrorList m_errors;
+	ErrorList m_errorList;
+	ErrorReporter m_errorReporter;
 	bool m_metadataLiteralSources = false;
 	State m_stackState = Empty;
 };
diff --git a/libsolidity/interface/ErrorReporter.cpp b/libsolidity/interface/ErrorReporter.cpp
new file mode 100644
index 00000000..6e2667a5
--- /dev/null
+++ b/libsolidity/interface/ErrorReporter.cpp
@@ -0,0 +1,167 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Rhett <roadriverrail@gmail.com>
+ * @date 2017
+ * Error helper class.
+ */
+
+#include <libsolidity/interface/ErrorReporter.h>
+#include <libsolidity/ast/AST.h>
+#include <memory>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+
+ErrorReporter& ErrorReporter::operator=(ErrorReporter const& _errorReporter)
+{
+	if (&_errorReporter == this)
+		return *this;
+	m_errorList = _errorReporter.m_errorList;
+	return *this;
+}
+
+
+void ErrorReporter::warning(string const& _description)
+{
+	error(Error::Type::Warning, SourceLocation(), _description);
+}
+
+void ErrorReporter::warning(SourceLocation const& _location, string const& _description)
+{
+	error(Error::Type::Warning, _location, _description);
+}
+
+void ErrorReporter::error(Error::Type _type, SourceLocation const& _location, string const& _description)
+{
+	auto err = make_shared<Error>(_type);
+	*err <<
+		errinfo_sourceLocation(_location) <<
+		errinfo_comment(_description);
+
+	m_errorList.push_back(err);
+}
+
+void ErrorReporter::error(Error::Type _type, SourceLocation const& _location, SecondarySourceLocation const& _secondaryLocation, string const& _description)
+{
+	auto err = make_shared<Error>(_type);
+	*err <<
+		errinfo_sourceLocation(_location) <<
+		errinfo_secondarySourceLocation(_secondaryLocation) <<
+		errinfo_comment(_description);
+
+	m_errorList.push_back(err);
+}
+
+
+void ErrorReporter::fatalError(Error::Type _type, SourceLocation const& _location, string const& _description)
+{
+	error(_type, _location, _description);
+	BOOST_THROW_EXCEPTION(FatalError());
+}
+
+ErrorList const& ErrorReporter::errors() const
+{
+	return m_errorList;
+}
+
+void ErrorReporter::clear()
+{
+	m_errorList.clear();
+}
+
+void ErrorReporter::declarationError(SourceLocation const& _location, SecondarySourceLocation const&_secondaryLocation, string const& _description)
+{
+	error(
+		Error::Type::DeclarationError,
+		_location,
+		_secondaryLocation,
+		_description
+	);
+}
+
+void ErrorReporter::declarationError(SourceLocation const& _location, string const& _description)
+{
+	error(
+		Error::Type::DeclarationError,
+		_location,
+		_description
+	);
+}
+
+void ErrorReporter::fatalDeclarationError(SourceLocation const& _location, std::string const& _description)
+{
+	fatalError(
+		Error::Type::DeclarationError,
+		_location,
+		_description);
+}
+
+void ErrorReporter::parserError(SourceLocation const& _location, string const& _description)
+{
+	error(
+		Error::Type::ParserError,
+		_location,
+		_description
+	);
+}
+
+void ErrorReporter::fatalParserError(SourceLocation const& _location, string const& _description)
+{
+	fatalError(
+		Error::Type::ParserError,
+		_location,
+		_description
+	);
+}
+
+void ErrorReporter::syntaxError(SourceLocation const& _location, string const& _description)
+{
+	error(
+		Error::Type::SyntaxError,
+		_location,
+		_description
+	);
+}
+
+void ErrorReporter::typeError(SourceLocation const& _location, string const& _description)
+{
+	error(
+		Error::Type::TypeError,
+		_location,
+		_description
+	);
+}
+
+
+void ErrorReporter::fatalTypeError(SourceLocation const& _location, string const& _description)
+{
+	fatalError(Error::Type::TypeError,
+		_location,
+		_description
+	);
+}
+
+void ErrorReporter::docstringParsingError(string const& _description)
+{
+	error(
+		Error::Type::DocstringParsingError,
+		SourceLocation(),
+		_description
+	);
+}
diff --git a/libsolidity/interface/ErrorReporter.h b/libsolidity/interface/ErrorReporter.h
new file mode 100644
index 00000000..e5605d24
--- /dev/null
+++ b/libsolidity/interface/ErrorReporter.h
@@ -0,0 +1,102 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Rhett <roadriverrail@gmail.com>
+ * @date 2017
+ * Error reporting helper class.
+ */
+
+#pragma once
+
+#include <libsolidity/interface/Exceptions.h>
+#include <libevmasm/SourceLocation.h>
+
+namespace dev
+{
+namespace solidity
+{
+
+class ASTNode;
+
+class ErrorReporter
+{
+public:
+
+	ErrorReporter(ErrorList& _errors):
+		m_errorList(_errors) { }
+
+	ErrorReporter& operator=(ErrorReporter const& _errorReporter);
+
+	void warning(std::string const& _description = std::string());
+
+	void warning(
+		SourceLocation const& _location = SourceLocation(),
+		std::string const& _description = std::string()
+	);
+
+	void error(
+		Error::Type _type,
+		SourceLocation const& _location = SourceLocation(),
+		std::string const& _description = std::string()
+	);
+
+	void declarationError(
+		SourceLocation const& _location,
+		SecondarySourceLocation const& _secondaryLocation = SecondarySourceLocation(),
+		std::string const& _description = std::string()
+	);
+
+	void declarationError(
+		SourceLocation const& _location,
+		std::string const& _description = std::string()
+	);
+
+	void fatalDeclarationError(SourceLocation const& _location, std::string const& _description);
+
+	void parserError(SourceLocation const& _location, std::string const& _description);
+
+	void fatalParserError(SourceLocation const& _location, std::string const& _description);
+
+	void syntaxError(SourceLocation const& _location, std::string const& _description);
+
+	void typeError(SourceLocation const& _location, std::string const& _description);
+
+	void fatalTypeError(SourceLocation const& _location, std::string const& _description);
+
+	void docstringParsingError(std::string const& _location);
+
+	ErrorList const& errors() const;
+
+	void clear();
+
+private:
+	void error(Error::Type _type,
+		SourceLocation const& _location,
+		SecondarySourceLocation const& _secondaryLocation,
+		std::string const& _description = std::string());
+
+	void fatalError(Error::Type _type,
+		SourceLocation const& _location = SourceLocation(),
+		std::string const& _description = std::string());
+
+	ErrorList& m_errorList;
+};
+
+
+}
+}
+
diff --git a/libsolidity/interface/Exceptions.cpp b/libsolidity/interface/Exceptions.cpp
index c09180de..9f2a2d06 100644
--- a/libsolidity/interface/Exceptions.cpp
+++ b/libsolidity/interface/Exceptions.cpp
@@ -21,7 +21,6 @@
  */
 
 #include <libsolidity/interface/Exceptions.h>
-#include <libsolidity/interface/Utils.h>
 
 using namespace std;
 using namespace dev;
@@ -47,9 +46,6 @@ Error::Error(Type _type, SourceLocation const& _location, string const& _descrip
 	case Type::TypeError:
 		m_typeName = "TypeError";
 		break;
-	case Type::Why3TranslatorError:
-		m_typeName = "Why3TranslatorError";
-		break;
 	case Type::Warning:
 		m_typeName = "Warning";
 		break;
diff --git a/libsolidity/interface/Exceptions.h b/libsolidity/interface/Exceptions.h
index 0803d8cc..09301b10 100644
--- a/libsolidity/interface/Exceptions.h
+++ b/libsolidity/interface/Exceptions.h
@@ -25,6 +25,7 @@
 #include <string>
 #include <utility>
 #include <libdevcore/Exceptions.h>
+#include <libdevcore/Assertions.h>
 #include <libevmasm/SourceLocation.h>
 
 namespace dev
@@ -39,6 +40,16 @@ struct InternalCompilerError: virtual Exception {};
 struct FatalError: virtual Exception {};
 struct UnimplementedFeatureError: virtual Exception{};
 
+/// Assertion that throws an InternalCompilerError containing the given description if it is not met.
+#define solAssert(CONDITION, DESCRIPTION) \
+        assertThrow(CONDITION, ::dev::solidity::InternalCompilerError, DESCRIPTION)
+
+#define solUnimplementedAssert(CONDITION, DESCRIPTION) \
+        assertThrow(CONDITION, ::dev::solidity::UnimplementedFeatureError, DESCRIPTION)
+
+#define solUnimplemented(DESCRIPTION) \
+        solUnimplementedAssert(false, DESCRIPTION)
+
 class Error: virtual public Exception
 {
 public:
@@ -49,7 +60,6 @@ public:
 		ParserError,
 		TypeError,
 		SyntaxError,
-		Why3TranslatorError,
 		Warning
 	};
 
diff --git a/libsolidity/interface/InterfaceHandler.cpp b/libsolidity/interface/InterfaceHandler.cpp
deleted file mode 100644
index 6c1bb0c4..00000000
--- a/libsolidity/interface/InterfaceHandler.cpp
+++ /dev/null
@@ -1,197 +0,0 @@
-
-#include <libsolidity/interface/InterfaceHandler.h>
-#include <boost/range/irange.hpp>
-#include <libsolidity/ast/AST.h>
-#include <libsolidity/interface/CompilerStack.h>
-
-using namespace std;
-using namespace dev;
-using namespace dev::solidity;
-
-Json::Value InterfaceHandler::documentation(
-	ContractDefinition const& _contractDef,
-	DocumentationType _type
-)
-{
-	switch(_type)
-	{
-	case DocumentationType::NatspecUser:
-		return userDocumentation(_contractDef);
-	case DocumentationType::NatspecDev:
-		return devDocumentation(_contractDef);
-	case DocumentationType::ABIInterface:
-		return abiInterface(_contractDef);
-	}
-
-	BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Unknown documentation type"));
-}
-
-Json::Value InterfaceHandler::abiInterface(ContractDefinition const& _contractDef)
-{
-	Json::Value abi(Json::arrayValue);
-
-	for (auto it: _contractDef.interfaceFunctions())
-	{
-		auto externalFunctionType = it.second->interfaceFunctionType();
-		Json::Value method;
-		method["type"] = "function";
-		method["name"] = it.second->declaration().name();
-		method["constant"] = it.second->isConstant();
-		method["payable"] = it.second->isPayable();
-		method["inputs"] = formatTypeList(
-			externalFunctionType->parameterNames(),
-			externalFunctionType->parameterTypes(),
-			_contractDef.isLibrary()
-		);
-		method["outputs"] = formatTypeList(
-			externalFunctionType->returnParameterNames(),
-			externalFunctionType->returnParameterTypes(),
-			_contractDef.isLibrary()
-		);
-		abi.append(method);
-	}
-	if (_contractDef.constructor())
-	{
-		Json::Value method;
-		method["type"] = "constructor";
-		auto externalFunction = FunctionType(*_contractDef.constructor(), false).interfaceFunctionType();
-		solAssert(!!externalFunction, "");
-		method["payable"] = externalFunction->isPayable();
-		method["inputs"] = formatTypeList(
-			externalFunction->parameterNames(),
-			externalFunction->parameterTypes(),
-			_contractDef.isLibrary()
-		);
-		abi.append(method);
-	}
-	if (_contractDef.fallbackFunction())
-	{
-		auto externalFunctionType = FunctionType(*_contractDef.fallbackFunction(), false).interfaceFunctionType();
-		solAssert(!!externalFunctionType, "");
-		Json::Value method;
-		method["type"] = "fallback";
-		method["payable"] = externalFunctionType->isPayable();
-		abi.append(method);
-	}
-	for (auto const& it: _contractDef.interfaceEvents())
-	{
-		Json::Value event;
-		event["type"] = "event";
-		event["name"] = it->name();
-		event["anonymous"] = it->isAnonymous();
-		Json::Value params(Json::arrayValue);
-		for (auto const& p: it->parameters())
-		{
-			solAssert(!!p->annotation().type->interfaceType(false), "");
-			Json::Value input;
-			input["name"] = p->name();
-			input["type"] = p->annotation().type->interfaceType(false)->canonicalName(false);
-			input["indexed"] = p->isIndexed();
-			params.append(input);
-		}
-		event["inputs"] = params;
-		abi.append(event);
-	}
-
-	return abi;
-}
-
-Json::Value InterfaceHandler::userDocumentation(ContractDefinition const& _contractDef)
-{
-	Json::Value doc;
-	Json::Value methods(Json::objectValue);
-
-	for (auto const& it: _contractDef.interfaceFunctions())
-		if (it.second->hasDeclaration())
-			if (auto const* f = dynamic_cast<FunctionDefinition const*>(&it.second->declaration()))
-			{
-				string value = extractDoc(f->annotation().docTags, "notice");
-				if (!value.empty())
-				{
-					Json::Value user;
-					// since @notice is the only user tag if missing function should not appear
-					user["notice"] = Json::Value(value);
-					methods[it.second->externalSignature()] = user;
-				}
-			}
-	doc["methods"] = methods;
-
-	return doc;
-}
-
-Json::Value InterfaceHandler::devDocumentation(ContractDefinition const& _contractDef)
-{
-	Json::Value doc;
-	Json::Value methods(Json::objectValue);
-
-	auto author = extractDoc(_contractDef.annotation().docTags, "author");
-	if (!author.empty())
-		doc["author"] = author;
-	auto title = extractDoc(_contractDef.annotation().docTags, "title");
-	if (!title.empty())
-		doc["title"] = title;
-
-	for (auto const& it: _contractDef.interfaceFunctions())
-	{
-		if (!it.second->hasDeclaration())
-			continue;
-		Json::Value method;
-		if (auto fun = dynamic_cast<FunctionDefinition const*>(&it.second->declaration()))
-		{
-			auto dev = extractDoc(fun->annotation().docTags, "dev");
-			if (!dev.empty())
-				method["details"] = Json::Value(dev);
-
-			auto author = extractDoc(fun->annotation().docTags, "author");
-			if (!author.empty())
-				method["author"] = author;
-
-			auto ret = extractDoc(fun->annotation().docTags, "return");
-			if (!ret.empty())
-				method["return"] = ret;
-
-			Json::Value params(Json::objectValue);
-			auto paramRange = fun->annotation().docTags.equal_range("param");
-			for (auto i = paramRange.first; i != paramRange.second; ++i)
-				params[i->second.paramName] = Json::Value(i->second.content);
-
-			if (!params.empty())
-				method["params"] = params;
-
-			if (!method.empty())
-				// add the function, only if we have any documentation to add
-				methods[it.second->externalSignature()] = method;
-		}
-	}
-	doc["methods"] = methods;
-
-	return doc;
-}
-
-Json::Value InterfaceHandler::formatTypeList(
-	vector<string> const& _names,
-	vector<TypePointer> const& _types,
-	bool _forLibrary
-)
-{
-	Json::Value params(Json::arrayValue);
-	solAssert(_names.size() == _types.size(), "Names and types vector size does not match");
-	for (unsigned i = 0; i < _names.size(); ++i)
-	{
-		solAssert(_types[i], "");
-		Json::Value param;
-		param["name"] = _names[i];
-		param["type"] = _types[i]->canonicalName(_forLibrary);
-		params.append(param);
-	}
-	return params;
-}
-
-string InterfaceHandler::extractDoc(multimap<string, DocTag> const& _tags, string const& _name)
-{
-	string value;
-	auto range = _tags.equal_range(_name);
-	for (auto i = range.first; i != range.second; i++)
-		value += i->second.content;
-	return value;
-}
diff --git a/libsolidity/interface/Natspec.cpp b/libsolidity/interface/Natspec.cpp
new file mode 100644
index 00000000..70486e23
--- /dev/null
+++ b/libsolidity/interface/Natspec.cpp
@@ -0,0 +1,130 @@
+/*
+        This file is part of solidity.
+
+        solidity is free software: you can redistribute it and/or modify
+        it under the terms of the GNU General Public License as published by
+        the Free Software Foundation, either version 3 of the License, or
+        (at your option) any later version.
+
+        solidity is distributed in the hope that it will be useful,
+        but WITHOUT ANY WARRANTY; without even the implied warranty of
+        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+        GNU General Public License for more details.
+
+        You should have received a copy of the GNU General Public License
+        along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Lefteris <lefteris@ethdev.com>
+ * @date 2014
+ * Takes the parsed AST and produces the Natspec documentation:
+ * https://github.com/ethereum/wiki/wiki/Ethereum-Natural-Specification-Format
+ *
+ * Can generally deal with JSON files
+ */
+
+#include <libsolidity/interface/Natspec.h>
+#include <boost/range/irange.hpp>
+#include <libsolidity/ast/AST.h>
+#include <libsolidity/interface/CompilerStack.h>
+
+using namespace std;
+using namespace dev;
+using namespace dev::solidity;
+
+Json::Value Natspec::documentation(
+	ContractDefinition const& _contractDef,
+	DocumentationType _type
+)
+{
+	switch(_type)
+	{
+	case DocumentationType::NatspecUser:
+		return userDocumentation(_contractDef);
+	case DocumentationType::NatspecDev:
+		return devDocumentation(_contractDef);
+	}
+
+	BOOST_THROW_EXCEPTION(InternalCompilerError() << errinfo_comment("Unknown documentation type"));
+}
+
+Json::Value Natspec::userDocumentation(ContractDefinition const& _contractDef)
+{
+	Json::Value doc;
+	Json::Value methods(Json::objectValue);
+
+	for (auto const& it: _contractDef.interfaceFunctions())
+		if (it.second->hasDeclaration())
+			if (auto const* f = dynamic_cast<FunctionDefinition const*>(&it.second->declaration()))
+			{
+				string value = extractDoc(f->annotation().docTags, "notice");
+				if (!value.empty())
+				{
+					Json::Value user;
+					// since @notice is the only user tag if missing function should not appear
+					user["notice"] = Json::Value(value);
+					methods[it.second->externalSignature()] = user;
+				}
+			}
+	doc["methods"] = methods;
+
+	return doc;
+}
+
+Json::Value Natspec::devDocumentation(ContractDefinition const& _contractDef)
+{
+	Json::Value doc;
+	Json::Value methods(Json::objectValue);
+
+	auto author = extractDoc(_contractDef.annotation().docTags, "author");
+	if (!author.empty())
+		doc["author"] = author;
+	auto title = extractDoc(_contractDef.annotation().docTags, "title");
+	if (!title.empty())
+		doc["title"] = title;
+
+	for (auto const& it: _contractDef.interfaceFunctions())
+	{
+		if (!it.second->hasDeclaration())
+			continue;
+		Json::Value method;
+		if (auto fun = dynamic_cast<FunctionDefinition const*>(&it.second->declaration()))
+		{
+			auto dev = extractDoc(fun->annotation().docTags, "dev");
+			if (!dev.empty())
+				method["details"] = Json::Value(dev);
+
+			auto author = extractDoc(fun->annotation().docTags, "author");
+			if (!author.empty())
+				method["author"] = author;
+
+			auto ret = extractDoc(fun->annotation().docTags, "return");
+			if (!ret.empty())
+				method["return"] = ret;
+
+			Json::Value params(Json::objectValue);
+			auto paramRange = fun->annotation().docTags.equal_range("param");
+			for (auto i = paramRange.first; i != paramRange.second; ++i)
+				params[i->second.paramName] = Json::Value(i->second.content);
+
+			if (!params.empty())
+				method["params"] = params;
+
+			if (!method.empty())
+				// add the function, only if we have any documentation to add
+				methods[it.second->externalSignature()] = method;
+		}
+	}
+	doc["methods"] = methods;
+
+	return doc;
+}
+
+string Natspec::extractDoc(multimap<string, DocTag> const& _tags, string const& _name)
+{
+	string value;
+	auto range = _tags.equal_range(_name);
+	for (auto i = range.first; i != range.second; i++)
+		value += i->second.content;
+	return value;
+}
diff --git a/libsolidity/interface/InterfaceHandler.h b/libsolidity/interface/Natspec.h
index 56927d44..bec9acd2 100644
--- a/libsolidity/interface/InterfaceHandler.h
+++ b/libsolidity/interface/Natspec.h
@@ -17,8 +17,7 @@
 /**
  * @author Lefteris <lefteris@ethdev.com>
  * @date 2014
- * Takes the parsed AST and produces the Natspec
- * documentation and the ABI interface
+ * Takes the parsed AST and produces the Natspec documentation:
  * https://github.com/ethereum/wiki/wiki/Ethereum-Natural-Specification-Format
  *
  * Can generally deal with JSON files
@@ -59,7 +58,7 @@ enum class CommentOwner
 	Function
 };
 
-class InterfaceHandler
+class Natspec
 {
 public:
 	/// Get the given type of documentation
@@ -71,10 +70,6 @@ public:
 		ContractDefinition const& _contractDef,
 		DocumentationType _type
 	);
-	/// Get the ABI Interface of the contract
-	/// @param _contractDef The contract definition
-	/// @return             A JSONrepresentation of the contract's ABI Interface
-	static Json::Value abiInterface(ContractDefinition const& _contractDef);
 	/// Get the User documentation of the contract
 	/// @param _contractDef The contract definition
 	/// @return             A JSON representation of the contract's user documentation
diff --git a/libsolidity/interface/StandardCompiler.cpp b/libsolidity/interface/StandardCompiler.cpp
index 223cc15d..e677afc8 100644
--- a/libsolidity/interface/StandardCompiler.cpp
+++ b/libsolidity/interface/StandardCompiler.cpp
@@ -115,14 +115,6 @@ StringMap createSourceList(Json::Value const& _input)
 	return sources;
 }
 
-Json::Value methodIdentifiers(ContractDefinition const& _contract)
-{
-	Json::Value methodIdentifiers(Json::objectValue);
-	for (auto const& it: _contract.interfaceFunctions())
-		methodIdentifiers[it.second->externalSignature()] = toHex(it.first.ref());
-	return methodIdentifiers;
-}
-
 Json::Value formatLinkReferences(std::map<size_t, std::string> const& linkReferences)
 {
 	Json::Value ret(Json::objectValue);
@@ -273,11 +265,9 @@ Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
 
 	auto scannerFromSourceName = [&](string const& _sourceName) -> solidity::Scanner const& { return m_compilerStack.scanner(_sourceName); };
 
-	bool success = false;
-
 	try
 	{
-		success = m_compilerStack.compile(optimize, optimizeRuns, libraries);
+		m_compilerStack.compile(optimize, optimizeRuns, libraries);
 
 		for (auto const& error: m_compilerStack.errors())
 		{
@@ -367,22 +357,26 @@ Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
 	if (errors.size() > 0)
 		output["errors"] = errors;
 
+	bool parsingSuccess = m_compilerStack.state() >= CompilerStack::State::ParsingSuccessful;
+	bool compilationSuccess = m_compilerStack.state() == CompilerStack::State::CompilationSuccessful;
+
 	/// Inconsistent state - stop here to receive error reports from users
-	if (!success && (errors.size() == 0))
+	if (!compilationSuccess && (errors.size() == 0))
 		return formatFatalError("InternalCompilerError", "No error reported, but compilation failed.");
 
 	output["sources"] = Json::objectValue;
 	unsigned sourceIndex = 0;
-	for (auto const& source: m_compilerStack.sourceNames())
+	for (auto const& source: parsingSuccess ? m_compilerStack.sourceNames() : vector<string>())
 	{
 		Json::Value sourceResult = Json::objectValue;
 		sourceResult["id"] = sourceIndex++;
-		sourceResult["legacyAST"] = ASTJsonConverter(m_compilerStack.ast(source), m_compilerStack.sourceIndices()).json();
+		sourceResult["ast"] = ASTJsonConverter(false, m_compilerStack.sourceIndices()).toJson(m_compilerStack.ast(source));
+		sourceResult["legacyAST"] = ASTJsonConverter(true, m_compilerStack.sourceIndices()).toJson(m_compilerStack.ast(source));
 		output["sources"][source] = sourceResult;
 	}
 
 	Json::Value contractsOutput = Json::objectValue;
-	for (string const& contractName: success ? m_compilerStack.contractNames() : vector<string>())
+	for (string const& contractName: compilationSuccess ? m_compilerStack.contractNames() : vector<string>())
 	{
 		size_t colon = contractName.find(':');
 		solAssert(colon != string::npos, "");
@@ -391,10 +385,10 @@ Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
 
 		// ABI, documentation and metadata
 		Json::Value contractData(Json::objectValue);
-		contractData["abi"] = m_compilerStack.metadata(contractName, DocumentationType::ABIInterface);
+		contractData["abi"] = m_compilerStack.contractABI(contractName);
 		contractData["metadata"] = m_compilerStack.onChainMetadata(contractName);
-		contractData["userdoc"] = m_compilerStack.metadata(contractName, DocumentationType::NatspecUser);
-		contractData["devdoc"] = m_compilerStack.metadata(contractName, DocumentationType::NatspecDev);
+		contractData["userdoc"] = m_compilerStack.natspec(contractName, DocumentationType::NatspecUser);
+		contractData["devdoc"] = m_compilerStack.natspec(contractName, DocumentationType::NatspecDev);
 
 		// EVM
 		Json::Value evmData(Json::objectValue);
@@ -403,7 +397,7 @@ Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
 		m_compilerStack.streamAssembly(tmp, contractName, createSourceList(_input), false);
 		evmData["assembly"] = tmp.str();
 		evmData["legacyAssembly"] = m_compilerStack.streamAssembly(tmp, contractName, createSourceList(_input), true);
-		evmData["methodIdentifiers"] = methodIdentifiers(m_compilerStack.contractDefinition(contractName));
+		evmData["methodIdentifiers"] = m_compilerStack.methodIdentifiers(contractName);
 		evmData["gasEstimates"] = m_compilerStack.gasEstimates(contractName);
 
 		evmData["bytecode"] = collectEVMObject(
diff --git a/libsolidity/interface/Utils.h b/libsolidity/interface/Utils.h
deleted file mode 100644
index 0027759c..00000000
--- a/libsolidity/interface/Utils.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
-	This file is part of solidity.
-
-	solidity is free software: you can redistribute it and/or modify
-	it under the terms of the GNU General Public License as published by
-	the Free Software Foundation, either version 3 of the License, or
-	(at your option) any later version.
-
-	solidity is distributed in the hope that it will be useful,
-	but WITHOUT ANY WARRANTY; without even the implied warranty of
-	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-	GNU General Public License for more details.
-
-	You should have received a copy of the GNU General Public License
-	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
-*/
-/**
- * @author Christian <c@ethdev.com>
- * @date 2014
- * Solidity Utilities.
- */
-
-#pragma once
-
-#include <libdevcore/Assertions.h>
-#include <libsolidity/interface/Exceptions.h>
-
-namespace dev
-{
-namespace solidity
-{
-struct InternalCompilerError;
-struct UnimplementedFeatureError;
-}
-}
-
-/// Assertion that throws an InternalCompilerError containing the given description if it is not met.
-#define solAssert(CONDITION, DESCRIPTION) \
-	assertThrow(CONDITION, ::dev::solidity::InternalCompilerError, DESCRIPTION)
-
-#define solUnimplementedAssert(CONDITION, DESCRIPTION) \
-	assertThrow(CONDITION, ::dev::solidity::UnimplementedFeatureError, DESCRIPTION)
-
-#define solUnimplemented(DESCRIPTION) \
-	solUnimplementedAssert(false, DESCRIPTION)
diff --git a/libsolidity/interface/Version.cpp b/libsolidity/interface/Version.cpp
index 0d23f9c3..a35bfd29 100644
--- a/libsolidity/interface/Version.cpp
+++ b/libsolidity/interface/Version.cpp
@@ -24,7 +24,7 @@
 #include <string>
 #include <libdevcore/CommonData.h>
 #include <libdevcore/Common.h>
-#include <libsolidity/interface/Utils.h>
+#include <libsolidity/interface/Exceptions.h>
 #include <solidity/BuildInfo.h>
 
 using namespace dev;