David Blaikie 5c43245bf4 Provide a "None" value for convenience when using Optional<T>()
This implementation of NoneType/None does have some holes but I haven't
found one that doesn't - open to improvement.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175696 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21 00:27:28 +00:00

28 lines
844 B
C++

//===-- None.h - Simple null value for implicit construction ------*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file provides None, an enumerant for use in implicit constructors
// of various (usually templated) types to make such construction more
// terse.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_ADT_NONE_H
#define LLVM_ADT_NONE_H
namespace llvm {
/// \brief A simple null object to allow implicit construction of Optional<T>
/// and similar types without having to spell out the specialization's name.
enum NoneType {
None
};
}
#endif