/*
This file is part of cpp-ethereum.
cpp-ethereum 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.
cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Solidity abstract syntax tree.
*/
#pragma once
#include <string>
#include <vector>
#include <memory>
#include <boost/noncopyable.hpp>
#include <libsolidity/ASTForward.h>
#include <libsolidity/BaseTypes.h>
#include <libsolidity/Token.h>
#include <libsolidity/Types.h>
#include <libsolidity/Exceptions.h>
namespace dev
{
namespace solidity
{
class ASTVisitor;
/**
* The root (abstract) class of the AST inheritance tree.
* It is possible to traverse all direct and indirect children of an AST node by calling
* accept, providing an ASTVisitor.
*/
class ASTNode: private boost::noncopyable
{
public:
explicit ASTNode(Location const& _location): m_location(_location) {}
virtual ~ASTNode() {}
virtual void accept(ASTVisitor& _visitor) = 0;
template <class T>
static void listAccept(std::vector<ASTPointer<T>>& _list, ASTVisitor& _visitor)
{
for (ASTPointer<T>& element: _list)
element->accept(_visitor);
}
/// Returns the source code location of this node.
Location const& getLocation() const { return m_location; }
/// Creates a @ref TypeError exception and decorates it with the location of the node and
/// the given description
TypeError createTypeError(std::string const& _description);
///@{
///@name equality operators
/// Equality relies on the fact that nodes cannot be copied.
bool operator==(ASTNode const& _other) const { return this == &_other; }
bool operator!=(ASTNode const& _other) const { return !operator==(_other); }
///@}
private:
Location m_location;
};
/**
* Abstract AST class for a declaration (contract, function, struct, variable).
*/
class Declaration: public ASTNode
{
public:
Declaration(Location const& _location, ASTPointer<ASTString> const& _name):
ASTNode(_location), m_name(_name) {}
/// Returns the declared name.
const ASTString& getName() const { return *m_name; }
private:
ASTPointer<ASTString> m_name;
};
/**
* Definition of a contract. This is the only AST nodes where child nodes are not visited in
* document order. It first visits all struct declarations, then all variable declarations and
* finally all function declarations.
*/
class ContractDefinition: public Declaration
{
public:
ContractDefinition(Location const& _location,
ASTPointer<ASTString> const& _name,
std::vector<ASTPointer<StructDefinition>> const& _definedStructs,
std::vector<ASTPointer<VariableDeclaration>> const& _stateVariables,
std::vector<ASTPointer<FunctionDefinition>> const& _definedFunctions):
Declaration(_location, _name),
m_definedStructs(_definedStructs),
m_stateVariables(_stateVariables),
m_definedFunctions(_definedFunctions)
{}
virtual void accept(ASTVisitor& _visitor) override;
std::vector<ASTPointer<StructDefinition>> const& getDefinedStructs() { return m_definedStructs; }
std::vector<ASTPointer<VariableDeclaration>> const& getStateVariables() { return m_stateVariables; }
std::vector<ASTPointer<FunctionDefinition>> const& getDefinedFunctions() { return m_definedFunctions; }
private:
std::vector<ASTPointer<StructDefinition>> m_definedStructs;
std::vector<ASTPointer<VariableDeclaration>> m_stateVariables;
std::vector<ASTPointer<FunctionDefinition>> m_definedFunctions;
};
class StructDefinition: public Declaration
{
public:
StructDefinition(Location const& _location,
ASTPointer<ASTString> const& _name,
std::vector<ASTPointer<VariableDeclaration>> const& _members):
Declaration(_location, _name), m_members(_members) {}
virtual void accept(ASTVisitor& _visitor) override;
private:
std::vector<ASTPointer<VariableDeclaration>> m_members;
};
/**
* Parameter list, used as function parameter list and return list.
* None of the parameters is allowed to contain mappings (not even recursively
* inside structs), but (@todo) this is not yet enforced.
*/
class ParameterList: public ASTNode
{
public:
ParameterList(Location const& _location,
std::vector<ASTPointer<VariableDeclaration>> const& _parameters):
ASTNode(_location), m_parameters(_parameters) {}
virtual void accept(ASTVisitor& _visitor) override;
std::vector<ASTPointer<VariableDeclaration>> const& getParameters() { return m_parameters; }
private:
std::vector<ASTPointer<VariableDeclaration>> m_parameters;
};
class FunctionDefinition: public Declaration
{
public:
FunctionDefinition(Location const& _location, ASTPointer<ASTString> const& _name, bool _isPublic,
ASTPointer<ParameterList> const& _parameters,
bool _isDeclaredConst,
ASTPointer<ParameterList> const& _returnParameters,
ASTPointer<Block> const& _body):
Declaration(_location, _name), m_isPublic(_isPublic), m_parameters(_parameters),
m_isDeclaredConst(_isDeclaredConst), m_returnParameters(_returnParameters),
m_body(_body) {}
virtual void accept(ASTVisitor& _visitor) override;
bool isPublic() const { return m_isPublic; }
bool isDeclaredConst() const { return m_isDeclaredConst; }
std::vector<ASTPointer<VariableDeclaration>> const& getParameters() const { return m_parameters->getParameters(); }
ParameterList& getParameterList() { return *m_parameters; }
ASTPointer<ParameterList> const& getReturnParameterList() const { return m_returnParameters; }
Block& getBody() { return *m_body; }
private:
bool m_isPublic;
ASTPointer<ParameterList> m_parameters;
bool m_isDeclaredConst;
ASTPointer<ParameterList> m_returnParameters;
ASTPointer<Block> m_body;
};
/**
* Declaration of a variable. This can be used in various places, e.g. in function parameter
* lists, struct definitions and even function bodys.
*/
class VariableDeclaration: public Declaration
{
public:
VariableDeclaration(Location const& _location, ASTPointer<TypeName> const& _type,
ASTPointer<ASTString> const& _name):
Declaration(_location, _name), m_typeName(_type) {}
virtual void accept(ASTVisitor& _visitor) override;
bool isTypeGivenExplicitly() const { return bool(m_typeName); }
TypeName* getTypeName() const { return m_typeName.get(); }
/// Returns the declared or inferred type. Can be an empty pointer if no type was explicitly
/// declared and there is no assignment to the variable that fixes the type.
std::shared_ptr<Type const> const& getType() const { return m_type; }
void setType(std::shared_ptr<Type const> const& _type) { m_type = _type; }
private:
ASTPointer<TypeName> m_typeName; ///< can be empty ("var")
std::shared_ptr<Type const> m_type; ///< derived type, initially empty
};
/// Types
/// @{
/**
* Abstract base class of a type name, can be any built-in or user-defined type.
*/
class TypeName: public ASTNode
{
public:
explicit TypeName(Location const& _location): ASTNode(_location) {}
virtual void accept(ASTVisitor& _visitor) override;
/// Retrieve the element of the type hierarchy this node refers to. Can return an empty shared
/// pointer until the types have been resolved using the @ref NameAndTypeResolver.
virtual std::shared_ptr<Type> toType() = 0;
};
/**
* Any pre-defined type name represented by a single keyword, i.e. it excludes mappings,
* contracts, functions, etc.
*/
class ElementaryTypeName: public TypeName
{
public:
explicit ElementaryTypeName(Location const& _location, Token::Value _type):
TypeName(_location), m_type(_type) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual std::shared_ptr<Type> toType() override { return Type::fromElementaryTypeName(m_type); }
Token::Value getTypeName() const { return m_type; }
private:
Token::Value m_type;
};
/**
* Name referring to a user-defined type (i.e. a struct).
* @todo some changes are necessary if this is also used to refer to contract types later
*/
class UserDefinedTypeName: public TypeName
{
public:
UserDefinedTypeName(Location const& _location, ASTPointer<ASTString> const& _name):
TypeName(_location), m_name(_name) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual std::shared_ptr<Type> toType() override { return Type::fromUserDefinedTypeName(*this); }
const ASTString& getName() const { return *m_name; }
void setReferencedStruct(StructDefinition& _referencedStruct) { m_referencedStruct = &_referencedStruct; }
StructDefinition const* getReferencedStruct() const { return m_referencedStruct; }
private:
ASTPointer<ASTString> m_name;
StructDefinition* m_referencedStruct;
};
/**
* A mapping type. Its source form is "mapping('keyType' => 'valueType')"
*/
class Mapping: public TypeName
{
public:
Mapping(Location const& _location, ASTPointer<ElementaryTypeName> const& _keyType,
ASTPointer<TypeName> const& _valueType):
TypeName(_location), m_keyType(_keyType), m_valueType(_valueType) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual std::shared_ptr<Type> toType() override { return Type::fromMapping(*this); }
private:
ASTPointer<ElementaryTypeName> m_keyType;
ASTPointer<TypeName> m_valueType;
};
/// @}
/// Statements
/// @{
/**
* Abstract base class for statements.
*/
class Statement: public ASTNode
{
public:
explicit Statement(Location const& _location): ASTNode(_location) {}
virtual void accept(ASTVisitor& _visitor) override;
/// Check all type requirements, throws exception if some requirement is not met.
/// This includes checking that operators are applicable to their arguments but also that
/// the number of function call arguments matches the number of formal parameters and so forth.
virtual void checkTypeRequirements() = 0;
protected:
/// Helper function, check that the inferred type for @a _expression is @a _expectedType or at
/// least implicitly convertible to @a _expectedType. If not, throw exception.
void expectType(Expression& _expression, Type const& _expectedType);
};
/**
* Brace-enclosed block containing zero or more statements.
*/
class Block: public Statement
{
public:
Block(Location const& _location, std::vector<ASTPointer<Statement>> const& _statements):
Statement(_location), m_statements(_statements) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
private:
std::vector<ASTPointer<Statement>> m_statements;
};
/**
* If-statement with an optional "else" part. Note that "else if" is modeled by having a new
* if-statement as the false (else) body.
*/
class IfStatement: public Statement
{
public:
IfStatement(Location const& _location, ASTPointer<Expression> const& _condition,
ASTPointer<Statement> const& _trueBody, ASTPointer<Statement> const& _falseBody):
Statement(_location),
m_condition(_condition), m_trueBody(_trueBody), m_falseBody(_falseBody) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
private:
ASTPointer<Expression> m_condition;
ASTPointer<Statement> m_trueBody;
ASTPointer<Statement> m_falseBody; //< "else" part, optional
};
/**
* Statement in which a break statement is legal.
* @todo actually check this requirement.
*/
class BreakableStatement: public Statement
{
public:
BreakableStatement(Location const& _location): Statement(_location) {}
virtual void accept(ASTVisitor& _visitor) override;
};
class WhileStatement: public BreakableStatement
{
public:
WhileStatement(Location const& _location, ASTPointer<Expression> const& _condition,
ASTPointer<Statement> const& _body):
BreakableStatement(_location), m_condition(_condition), m_body(_body) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
private:
ASTPointer<Expression> m_condition;
ASTPointer<Statement> m_body;
};
class Continue: public Statement
{
public:
Continue(Location const& _location): Statement(_location) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
};
class Break: public Statement
{
public:
Break(Location const& _location): Statement(_location) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
};
class Return: public Statement
{
public:
Return(Location const& _location, ASTPointer<Expression> _expression):
Statement(_location), m_expression(_expression) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
void setFunctionReturnParameters(ParameterList& _parameters) { m_returnParameters = &_parameters; }
private:
ASTPointer<Expression> m_expression; //< value to return, optional
/// Pointer to the parameter list of the function, filled by the @ref NameAndTypeResolver.
ParameterList* m_returnParameters;
};
/**
* Definition of a variable as a statement inside a function. It requires a type name (which can
* also be "var") but the actual assignment can be missing.
* Examples: var a = 2; uint256 a;
*/
class VariableDefinition: public Statement
{
public:
VariableDefinition(Location const& _location, ASTPointer<VariableDeclaration> _variable,
ASTPointer<Expression> _value):
Statement(_location), m_variable(_variable), m_value(_value) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
private:
ASTPointer<VariableDeclaration> m_variable;
ASTPointer<Expression> m_value; ///< the assigned value, can be missing
};
/**
* An expression, i.e. something that has a value (which can also be of type "void" in case
* of function calls).
*/
class Expression: public Statement
{
public:
Expression(Location const& _location): Statement(_location) {}
std::shared_ptr<Type const> const& getType() const { return m_type; }
protected:
/// Inferred type of the expression, only filled after a call to checkTypeRequirements().
std::shared_ptr<Type const> m_type;
};
/// @}
/// Expressions
/// @{
/**
* Assignment, can also be a compound assignment.
* Examples: (a = 7 + 8) or (a *= 2)
*/
class Assignment: public Expression
{
public:
Assignment(Location const& _location, ASTPointer<Expression> const& _leftHandSide,
Token::Value _assignmentOperator, ASTPointer<Expression> const& _rightHandSide):
Expression(_location), m_leftHandSide(_leftHandSide),
m_assigmentOperator(_assignmentOperator), m_rightHandSide(_rightHandSide) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
Expression& getLeftHandSide() const { return *m_leftHandSide; }
Token::Value getAssignmentOperator() const { return m_assigmentOperator; }
Expression& getRightHandSide() const { return *m_rightHandSide; }
private:
ASTPointer<Expression> m_leftHandSide;
Token::Value m_assigmentOperator;
ASTPointer<Expression> m_rightHandSide;
};
/**
* Operation involving a unary operator, pre- or postfix.
* Examples: ++i, delete x or !true
*/
class UnaryOperation: public Expression
{
public:
UnaryOperation(Location const& _location, Token::Value _operator,
ASTPointer<Expression> const& _subExpression, bool _isPrefix):
Expression(_location), m_operator(_operator),
m_subExpression(_subExpression), m_isPrefix(_isPrefix) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
Token::Value getOperator() const { return m_operator; }
bool isPrefixOperation() const { return m_isPrefix; }
private:
Token::Value m_operator;
ASTPointer<Expression> m_subExpression;
bool m_isPrefix;
};
/**
* Operation involving a binary operator.
* Examples: 1 + 2, true && false or 1 <= 4
*/
class BinaryOperation: public Expression
{
public:
BinaryOperation(Location const& _location, ASTPointer<Expression> const& _left,
Token::Value _operator, ASTPointer<Expression> const& _right):
Expression(_location), m_left(_left), m_operator(_operator), m_right(_right) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
Expression& getLeftExpression() const { return *m_left; }
Expression& getRightExpression() const { return *m_right; }
Token::Value getOperator() const { return m_operator; }
private:
ASTPointer<Expression> m_left;
Token::Value m_operator;
ASTPointer<Expression> m_right;
std::shared_ptr<Type const> m_commonType;
};
/**
* Can be ordinary function call, type cast or struct construction.
*/
class FunctionCall: public Expression
{
public:
FunctionCall(Location const& _location, ASTPointer<Expression> const& _expression,
std::vector<ASTPointer<Expression>> const& _arguments):
Expression(_location), m_expression(_expression), m_arguments(_arguments) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
/// Returns true if this is not an actual function call, but an explicit type conversion
/// or constructor call.
bool isTypeConversion() const;
private:
ASTPointer<Expression> m_expression;
std::vector<ASTPointer<Expression>> m_arguments;
};
/**
* Access to a member of an object. Example: x.name
*/
class MemberAccess: public Expression
{
public:
MemberAccess(Location const& _location, ASTPointer<Expression> _expression,
ASTPointer<ASTString> const& _memberName):
Expression(_location), m_expression(_expression), m_memberName(_memberName) {}
virtual void accept(ASTVisitor& _visitor) override;
const ASTString& getMemberName() const { return *m_memberName; }
virtual void checkTypeRequirements() override;
private:
ASTPointer<Expression> m_expression;
ASTPointer<ASTString> m_memberName;
};
/**
* Index access to an array. Example: a[2]
*/
class IndexAccess: public Expression
{
public:
IndexAccess(Location const& _location, ASTPointer<Expression> const& _base,
ASTPointer<Expression> const& _index):
Expression(_location), m_base(_base), m_index(_index) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
private:
ASTPointer<Expression> m_base;
ASTPointer<Expression> m_index;
};
/**
* Primary expression, i.e. an expression that cannot be divided any further. Examples are literals
* or variable references.
*/
class PrimaryExpression: public Expression
{
public:
PrimaryExpression(Location const& _location): Expression(_location) {}
};
/**
* An identifier, i.e. a reference to a declaration by name like a variable or function.
*/
class Identifier: public PrimaryExpression
{
public:
Identifier(Location const& _location, ASTPointer<ASTString> const& _name):
PrimaryExpression(_location), m_name(_name) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
ASTString const& getName() const { return *m_name; }
void setReferencedDeclaration(Declaration& _referencedDeclaration) { m_referencedDeclaration = &_referencedDeclaration; }
Declaration* getReferencedDeclaration() { return m_referencedDeclaration; }
private:
ASTPointer<ASTString> m_name;
/// Declaration the name refers to.
Declaration* m_referencedDeclaration;
};
/**
* An elementary type name expression is used in expressions like "a = uint32(2)" to change the
* type of an expression explicitly. Here, "uint32" is the elementary type name expression and
* "uint32(2)" is a @ref FunctionCall.
*/
class ElementaryTypeNameExpression: public PrimaryExpression
{
public:
ElementaryTypeNameExpression(Location const& _location, Token::Value _typeToken):
PrimaryExpression(_location), m_typeToken(_typeToken) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
Token::Value getTypeToken() const { return m_typeToken; }
private:
Token::Value m_typeToken;
};
/**
* A literal string or number. @see Type::literalToBigEndian is used to actually parse its value.
*/
class Literal: public PrimaryExpression
{
public:
Literal(Location const& _location, Token::Value _token, ASTPointer<ASTString> const& _value):
PrimaryExpression(_location), m_token(_token), m_value(_value) {}
virtual void accept(ASTVisitor& _visitor) override;
virtual void checkTypeRequirements() override;
Token::Value getToken() const { return m_token; }
/// @returns the non-parsed value of the literal
ASTString const& getValue() const { return *m_value; }
private:
Token::Value m_token;
ASTPointer<ASTString> m_value;
};
/// @}
}
}
