path: root/include/clang/AST/Expr.h

//===--- Expr.h - Classes for representing expressions ----------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//  This file defines the Expr interface and subclasses.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_AST_EXPR_H
#define LLVM_CLANG_AST_EXPR_H

#include "clang/AST/Stmt.h"
#include "clang/AST/Type.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclObjC.h"
#include "clang/Basic/IdentifierTable.h"
#include "llvm/ADT/APSInt.h"
#include "llvm/ADT/APFloat.h"

namespace clang {
  class IdentifierInfo;
  class Selector;
  class Decl;
  class ASTContext;
  
/// Expr - This represents one expression.  Note that Expr's are subclasses of
/// Stmt.  This allows an expression to be transparently used any place a Stmt
/// is required.
///
class Expr : public Stmt {
  QualType TR;
protected:
  Expr(StmtClass SC, QualType T) : Stmt(SC), TR(T) {}
public:  
  QualType getType() const { return TR; }
  void setType(QualType t) { TR = t; }

  /// SourceLocation tokens are not useful in isolation - they are low level
  /// value objects created/interpreted by SourceManager. We assume AST
  /// clients will have a pointer to the respective SourceManager.
  virtual SourceRange getSourceRange() const = 0;

  /// getExprLoc - Return the preferred location for the arrow when diagnosing
  /// a problem with a generic expression.
  virtual SourceLocation getExprLoc() const { return getLocStart(); }
  
  /// hasLocalSideEffect - Return true if this immediate expression has side
  /// effects, not counting any sub-expressions.
  bool hasLocalSideEffect() const;
  
  /// isLvalue - C99 6.3.2.1: an lvalue is an expression with an object type or
  /// incomplete type other than void. Nonarray expressions that can be lvalues:
  ///  - name, where name must be a variable
  ///  - e[i]
  ///  - (e), where e must be an lvalue
  ///  - e.name, where e must be an lvalue
  ///  - e->name
  ///  - *e, the type of e cannot be a function type
  ///  - string-constant
  ///  - reference type [C++ [expr]]
  ///
  enum isLvalueResult {
    LV_Valid,
    LV_NotObjectType,
    LV_IncompleteVoidType,
    LV_DuplicateVectorComponents,
    LV_InvalidExpression
  };
  isLvalueResult isLvalue