1 files changed, 18 insertions, 6 deletions

diff --git a/tools/gn/functions.h b/tools/gn/functions.h
index b55ff3a..351861b 100644
--- a/tools/gn/functions.h
+++ b/tools/gn/functions.h
@@ -18,7 +18,6 @@ class Label;
 class ListNode;
 class ParseNode;
 class Scope;
-class SourceDir;
 class Token;
 class Value;
 
@@ -26,6 +25,14 @@ class Value;
 
 namespace functions {
 
+// This type of function invocation has no block and evaluates its arguments
+// itself rather than taking a pre-executed list. This allows us to implement
+// certain built-in functions.
+typedef Value (*SelfEvaluatingArgsFunction)(Scope* scope,
+                                            const FunctionCallNode* function,
+                                            const ListNode* args_list,
+                                            Err* err);
+
 // This type of function invocation takes a block node that it will execute.
 typedef Value (*GenericBlockFunction)(Scope* scope,
                                       const FunctionCallNode* function,
@@ -92,6 +99,13 @@ Value RunDeclareArgs(Scope* scope,
                      BlockNode* block,
                      Err* err);
 
+extern const char kDefined[];
+extern const char kDefined_Help[];
+Value RunDefined(Scope* scope,
+                 const FunctionCallNode* function,
+                 const ListNode* args_list,
+                 Err* err);
+
 extern const char kExecScript[];
 extern const char kExecScript_Help[];
 Value RunExecScript(Scope* scope,
@@ -234,10 +248,12 @@ Value RunWriteFile(Scope* scope,
 // which indicates the type of function it is.
 struct FunctionInfo {
   FunctionInfo();
+  FunctionInfo(SelfEvaluatingArgsFunction seaf, const char* in_help);
   FunctionInfo(GenericBlockFunction gbf, const char* in_help);
   FunctionInfo(ExecutedBlockFunction ebf, const char* in_help);
   FunctionInfo(NoBlockFunction nbf, const char* in_help);
 
+  SelfEvaluatingArgsFunction self_evaluating_args_runner;
   GenericBlockFunction generic_block_runner;
   ExecutedBlockFunction executed_block_runner;
   NoBlockFunction no_block_runner;
@@ -253,7 +269,7 @@ const FunctionInfoMap& GetFunctions();
 // Runs the given function.
 Value RunFunction(Scope* scope,
                   const FunctionCallNode* function,
-                  const std::vector<Value>& args,
+                  const ListNode* args_list,
                   BlockNode* block,  // Optional.
                   Err* err);
 
@@ -300,10 +316,6 @@ bool EnsureSingleStringArg(const FunctionCallNode* function,
                            const std::vector<Value>& args,
                            Err* err);
 
-// Returns the source directory for the file comtaining the given function
-// invocation.
-const SourceDir& SourceDirForFunctionCall(const FunctionCallNode* function);
-
 // Returns the name of the toolchain for the given scope.
 const Label& ToolchainLabelForScope(const Scope* scope);