1 //===--- Printable.h - Print function helpers -------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines the Printable struct. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_SUPPORT_PRINTABLE_H 15 #define LLVM_SUPPORT_PRINTABLE_H 16 17 #include <functional> 18 19 namespace llvm { 20 21 class raw_ostream; 22 23 /// Simple wrapper around std::function<void(raw_ostream&)>. 24 /// This class is useful to construct print helpers for raw_ostream. 25 /// 26 /// Example: 27 /// Printable PrintRegister(unsigned Register) { 28 /// return Printable([Register](raw_ostream &OS) { 29 /// OS << getRegisterName(Register); 30 /// } 31 /// } 32 /// ... OS << PrintRegister(Register); ... 33 /// 34 /// Implementation note: Ideally this would just be a typedef, but doing so 35 /// leads to operator << being ambiguous as function has matching constructors 36 /// in some STL versions. I have seen the problem on gcc 4.6 libstdc++ and 37 /// microsoft STL. 38 class Printable { 39 public: 40 std::function<void(raw_ostream &OS)> Print; 41 Printable(std::function<void(raw_ostream &OS)> Print) 42 : Print(std::move(Print)) {} 43 }; 44 45 static inline raw_ostream &operator<<(raw_ostream &OS, const Printable &P) { 46 P.Print(OS); 47 return OS; 48 } 49 50 } 51 52 #endif 53
