diff options
Diffstat (limited to 'include/clang/AST/Expr.h')
| -rw-r--r-- | include/clang/AST/Expr.h | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/include/clang/AST/Expr.h b/include/clang/AST/Expr.h index 3050bf9a2e..041446d689 100644 --- a/include/clang/AST/Expr.h +++ b/include/clang/AST/Expr.h @@ -127,19 +127,25 @@ public: bool isUnusedResultAWarning(SourceLocation &Loc, SourceRange &R1, SourceRange &R2, ASTContext &Ctx) 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]] - /// - b ? x : y, where x and y are lvalues of suitable types [C++] + /// isLValue - True if this expression is an "l-value" according to + /// the rules of the current language. C and C++ give somewhat + /// different rules for this concept, but in general, the result of + /// an l-value expression identifies a specific object whereas the + /// result of an r-value expression is a value detached from any + /// specific storage. /// - enum isLvalueResult { + /// C++0x divides the concept of "r-value" into pure r-values + /// ("pr-values") and so-called expiring values ("x-values"), which + /// identify specific objects that can be safely cannibalized for + /// their resources. This is an unfortunate abuse of terminology on + /// the part of the C++ committee. In Clang, when we say "r-value", + /// we generally mean a pr-value. + bool isLValue() const { return getValueKind() == VK_LValue; } + bool isRValue() const { return getValueKind() == VK_RValue; } + bool isXValue() const { return getValueKind() == VK_XValue; } + bool isGLValue() const { return getValueKind() != VK_RValue; } + + enum LValueClassification { LV_Valid, LV_NotObjectType, LV_IncompleteVoidType, @@ -149,7 +155,8 @@ public: LV_SubObjCPropertySetting, LV_ClassTemporary }; - isLvalueResult isLvalue(ASTContext &Ctx) const; + /// Reasons why an expression might not be an l-value. + LValueClassification ClassifyLValue(ASTContext &Ctx) const; /// isModifiableLvalue - C99 6.3.2.1: an lvalue that does not have array type, /// does not have an incomplete type, does not have a const-qualified type, |