LLVM API Documentation
Class which can simulate a type-safe variadic function. More...
#include <VariadicFunction.h>
Public Member Functions | |
ResultT | operator() () const |
Class which can simulate a type-safe variadic function.
The VariadicFunction class template makes it easy to define type-safe variadic functions where all arguments have the same type.
Suppose we need a variadic function like this:
ResultT Foo(const ArgT &A_0, const ArgT &A_1, ..., const ArgT &A_N);
Instead of many overloads of Foo(), we only need to define a helper function that takes an array of arguments:
ResultT FooImpl(ArrayRef<const ArgT *> Args) { 'Args[i]' is a pointer to the i-th argument passed to Foo(). ... }
and then define Foo() like this:
const VariadicFunction<ResultT, ArgT, FooImpl> Foo;
VariadicFunction takes care of defining the overloads of Foo().
Actually, Foo is a function object (i.e. functor) instead of a plain function. This object is stateless and its constructor/destructor does nothing, so it's safe to create global objects and call Foo(...) at any time.
Sometimes we need a variadic function to have some fixed leading arguments whose types may be different from that of the optional arguments. For example:
bool FullMatch(const StringRef &S, const RE &Regex, const ArgT &A_0, ..., const ArgT &A_N);
VariadicFunctionN is for such cases, where N is the number of fixed arguments. It is like VariadicFunction, except that it takes N more template arguments for the types of the fixed arguments:
bool FullMatchImpl(const StringRef &S, const RE &Regex, ArrayRef<const ArgT *> Args) { ... } const VariadicFunction2<bool, const StringRef&, const RE&, ArgT, FullMatchImpl> FullMatch;
Currently VariadicFunction and friends support up-to 3 fixed leading arguments and up-to 32 optional arguments.
Definition at line 106 of file VariadicFunction.h.
ResultT llvm::VariadicFunction< ResultT, ArgT, Func >::operator() | ( | ) | const [inline] |
Definition at line 107 of file VariadicFunction.h.
References llvm::None.