from __future__ import absolute_import, division, print_function

from string import Template

def replace_action(target, source, env):
  open(str(target[0]), 'w').write(Template(open(str(source[0]), 'r').read()).safe_substitute(env))
  return 0

def replace_string(target, source, env):
  return "building '%s' from '%s'" % (str(target[0]), str(source[0]))

def generate(env, **kw):
  action = env.Action(replace_action, replace_string)
  env['BUILDERS']['ScanReplace'] = env.Builder(action=action, src_suffix='.in', single_source=True)

def exists(env):
  return 1