Minor cleanup.

pylib/gyp/input.py

 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 from compiler.ast import Const
 from compiler.ast import Dict
 from compiler.ast import Discard
 from compiler.ast import List
 from compiler.ast import Module
 from compiler.ast import Node
@@ skipping 1055 matching lines @@
       # Make a copy of the variables dict so that it won't influence anything
       # outside of its own scope.
       ProcessVariablesAndConditionsInDict(item, phase, variables, build_file)
     elif isinstance(item, list):
       ProcessVariablesAndConditionsInList(item, phase, variables, build_file)
     elif isinstance(item, str):
       expanded = ExpandVariables(item, phase, variables, build_file)
       if isinstance(expanded, str) or isinstance(expanded, int):
         the_list[index] = expanded
       elif isinstance(expanded, list):
-        del the_list[index]
-        for expanded_item in expanded:
-          the_list.insert(index, expanded_item)
-          index = index + 1
+        the_list[index:index+1] = expanded
+        index += len(expanded)
 
         # index now identifies the next item to examine.  Continue right now
         # without falling into the index increment below.
         continue
       else:
         raise ValueError, \
               'Variable expansion in this context permits strings and ' + \
               'lists only, found ' + expanded.__class__.__name__ + ' at ' + \
               index
     elif not isinstance(item, int):
@@ skipping 1388 matching lines @@
     ValidateRunAsInTarget(target, target_dict, build_file)
     ValidateActionsInTarget(target, target_dict, build_file)
 
   # Generators might not expect ints.  Turn them into strs.
   TurnIntIntoStrInDict(data)
 
   # TODO(mark): Return |data| for now because the generator needs a list of
   # build files that came in.  In the future, maybe it should just accept
   # a list, and not the whole data dict.
   return [flat_list, targets, data]