1 // Copyright (c) 2013 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 #include "tools/gn/functions.h" 6 #include "tools/gn/parse_tree.h" 7 #include "tools/gn/scope.h" 8 #include "tools/gn/value.h" 9 10 namespace functions { 11 12 const char kDefineRule[] = "define_rule"; 13 const char kDefileRule_Help[] = 14 "TODO(brettw) write this."; 15 16 Value RunDefineRule(Scope* scope, 17 const FunctionCallNode* function, 18 const std::vector<Value>& args, 19 BlockNode* block, 20 Err* err) { 21 // TODO(brettw) determine if the function is built-in and throw an error if 22 // it is. 23 if (args.size() != 1) { 24 *err = Err(function->function(), 25 "Need exactly one string arg to define_rule."); 26 return Value(); 27 } 28 if (!args[0].VerifyTypeIs(Value::STRING, err)) 29 return Value(); 30 std::string rule_name = args[0].string_value(); 31 32 const FunctionCallNode* existing_rule = scope->GetRule(rule_name); 33 if (existing_rule) { 34 *err = Err(function, "Duplicate rule definition.", 35 "A rule with this name was already defined."); 36 err->AppendSubErr(Err(existing_rule->function(), "Previous definition.")); 37 return Value(); 38 } 39 40 scope->AddRule(rule_name, function); 41 return Value(); 42 } 43 44 } // namespace functions 45
