template_emitter.h

C++ web template engine

// Copyright (c) 2007, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
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//
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// ---
// Author: Craig Silverstein
//
// When we expand a template, we expand into an abstract "emitter".
// This is typically a string, but could be a file-wrapper, or any
// other data structure that supports this very simple "append" API.

#ifndef TEMPLATE_TEMPLATE_EMITTER_H_
#define TEMPLATE_TEMPLATE_EMITTER_H_

#include <sys/types.h>     // for size_t
#include <string>

// NOTE: if you are statically linking the template library into your binary
// (rather than using the template .dll), set '/D CTEMPLATE_DLL_DECL='
// as a compiler flag in your project file to turn off the dllimports.
#ifndef CTEMPLATE_DLL_DECL
# define CTEMPLATE_DLL_DECL  __declspec(dllimport)
#endif

namespace google {

class CTEMPLATE_DLL_DECL ExpandEmitter {
 public:
  ExpandEmitter() {}
  virtual ~ExpandEmitter() {}
  virtual void Emit(char c) = 0;
  virtual void Emit(const std::string& s) = 0;
  virtual void Emit(const char* s) = 0;
  virtual void Emit(const char* s, size_t slen) = 0;
};


class CTEMPLATE_DLL_DECL StringEmitter : public ExpandEmitter {
  std::string* const outbuf_;
 public:
  StringEmitter(std::string* outbuf) : outbuf_(outbuf) {}
  virtual void Emit(char c) { *outbuf_ += c; }
  virtual void Emit(const std::string& s) { *outbuf_ += s; }
  virtual void Emit(const char* s) { *outbuf_ += s; }
  virtual void Emit(const char* s, size_t slen) { outbuf_->append(s, slen); }
};

}

#endif  // TEMPLATE_TEMPLATE_EMITTER_H_