tools/gn/template.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef TOOLS_GN_TEMPLATE_H_
   6 #define TOOLS_GN_TEMPLATE_H_
   7
   8 #include <vector>
   9
  10 #include "base/basictypes.h"
  11 #include "base/memory/ref_counted.h"
  12 #include "base/memory/scoped_ptr.h"
  13
  14 class BlockNode;
  15 class Err;
  16 class FunctionCallNode;
  17 class LocationRange;
  18 class Scope;
  19 class Value;
  20
  21 // Represents the information associated with a template() call in GN, which
  22 // includes a closure and the code to run when the template is invoked.
  23 //
  24 // This class is immutable so we can reference it from multiple threads without
  25 // locking. Normally, this will be assocated with a .gni file and then a
  26 // reference will be taken by each .gn file that imports it. These files might
  27 // execute the template in parallel.
  28 class Template : public base::RefCountedThreadSafe<Template> {
  29  public:
  30   // Makes a new closure based on the given scope.
  31   Template(const Scope* scope, const FunctionCallNode* def);
  32
  33   // Takes ownership of a previously-constructed closure.
  34   Template(scoped_ptr<Scope> closure, const FunctionCallNode* def);
  35
  36   // Invoke the template. The values correspond to the state of the code
  37   // invoking the template.
  38   Value Invoke(Scope* scope,
  39                const FunctionCallNode* invocation,
  40                const std::vector<Value>& args,
  41                BlockNode* block,
  42                Err* err) const;
  43
  44   // Returns the location range where this template was defined.
  45   LocationRange GetDefinitionRange() const;
  46
  47  private:
  48   friend class base::RefCountedThreadSafe<Template>;
  49
  50   Template();
  51   ~Template();
  52
  53   scoped_ptr<Scope> closure_;
  54   const FunctionCallNode* definition_;
  55 };
  56
  57 #endif  // TOOLS_GN_TEMPLATE_H_