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