Statespressions? (Re: Draft Pep (was: Re: Let's Talk About Lambda Functions!))

[Michael Hudson]

Duncan Booth <duncan at NOSPAMrcp.co.uk> writes:

> You can probably build a new code object using new.code(), but with 14 
> arguments to be passed in I can't be bothered showing an example.

I have this useful function lying around:

def copy_code_with_changes(codeobject,
                           argcount=None,
                           nlocals=None,
                           stacksize=None,
                           flags=None,
                           code=None,
                           consts=None,
                           names=None,
                           varnames=None,
                           filename=None,
                           name=None,
                           firstlineno=None,
                           lnotab=None):
    if argcount    is None: argcount    = codeobject.co_argcount
    if nlocals     is None: nlocals     = codeobject.co_nlocals
    if stacksize   is None: stacksize   = codeobject.co_stacksize
    if flags       is None: flags       = codeobject.co_flags
    if code        is None: code        = codeobject.co_code
    if consts      is None: consts      = codeobject.co_consts
    if names       is None: names       = codeobject.co_names
    if varnames    is None: varnames    = codeobject.co_varnames
    if filename    is None: filename    = codeobject.co_filename
    if name        is None: name        = codeobject.co_name
    if firstlineno is None: firstlineno = codeobject.co_firstlineno
    if lnotab      is None: lnotab      = codeobject.co_lnotab
    return new.code(argcount,
                    nlocals,
                    stacksize,
                    flags,
                    code,
                    consts,
                    names,
                    varnames,
                    filename,
                    name,
                    firstlineno,
                    lnotab)

So you can go

new_code = copy_code_with_changes(old_code, name="case a")

pychecker complains that it has too many arguments...

Cheers,
M.

-- 
  This makes it possible to pass complex object hierarchies to
  a C coder who thinks computer science has made no worthwhile
  advancements since the invention of the pointer.
                                       -- Gordon McMillan, 30 Jul 1998