def _get_value()

in static/downloads/ezt.py [0:0]

• 22 lines of code
• 10 McCabe index (conditional complexity)

def _get_value((refname, start, rest), ctx, filename, line_number):
  """(refname, start, rest) -> a prepared `value reference' (see above).
  ctx -> an execution context instance.

  Does a name space lookup within the template name space.  Active
  for blocks take precedence over data dictionary members with the
  same name.
  """
  if rest is None:
    # it was a string constant
    return start

  # get the starting object
  if ctx.for_index.has_key(start):
    list, idx = ctx.for_index[start]
    ob = list[idx]
  elif ctx.defines.has_key(start):
    ob = ctx.defines[start]
  elif hasattr(ctx.data, start):
    ob = getattr(ctx.data, start)
  else:
    raise UnknownReference(refname, filename, line_number)

  # walk the rest of the dotted reference
  for attr in rest:
    try:
      ob = getattr(ob, attr)
    except AttributeError:
      raise UnknownReference(refname, filename, line_number)

  # make sure we return a string instead of some various Python types
  if isinstance(ob, (IntType, FloatType, LongType)):
    return str(ob)
  if ob is None:
    return ''

  # string or a sequence
  return ob