[Python-ideas] Proposal for function expressions

[Mathias Panzenböck]

This seems to be a nice idea.
+0.5

	-panzi

On 07/13/2009 01:40 PM, Jan Kaliszewski wrote:
> Dear Pythonistas,
>
> It's my first post in the list, so let me introduce myself. My name is Jan
> Kaliszewski, I am a composer (studied in Frederic Chopin Academy of Music
> in Warsaw) and a programmer (currently working in Record System company on
> Anakonda -- ERP system being programmed in Python).
>
> Comming to the matter...
>
> 13-07-2009 Chris Perkins <chrisperkins99 at gmail.com>:
>
>> In other words, I think code that puts things in the opposite order
>> from the way you think of them is harder to read.
>>
>> Another example: if I'm thinking that what I want to do is "substitute
>> some stuff in a string", then I want to start by typing/reading
>> "re.sub(...)", and not "def some_made_up_name(...):"
>>
>> re.sub(pat, &, s) do(m):
>>     # several lines of code
>>
>> vs.
>>
>> def temp(m):
>>     # several lines of code
>> re.sub(pat, temp, s)
>>
>> The latter relegates the key line of code to the very last line,
>> making it harder to see at a glance what it does.
>>
>> So yes, the point of this really is just to allow you to write code
>> "in the right order".
>
> I like the idea of '&' (or another character/word in that role) -- but
> maybe it'd be enough to extend an existing feature: decorators with it,
> and to add possibility to use that special character/word as a function
> name after 'def'?
>
> E.g.:
>
> ###################
> # Networking
>
> dfr = twisted.whatever(...)
>
> # @dfr.addCallback(&) could be equivalent
> @dfr.addCallback
> def &(result):
>      handle(result)
>
> @dfr.addErrback
> def &(err):
>      handle_err(err)
>
> ###################
> # GUI (for some hypothetical library)
>
> @my_widget.add_button('Go').on('click', &)
> def &(evt):
>      if evt.ctrl_key:
>          do_something()
>      else:
>          do_other_stuff()
>
> # or, if we want to keep the result:
>
> @my_widget.add_button('Go').on('click', &)
> def button_clicked(evt):
>      if evt.ctrl_key:
>          do_something()
>      else:
>          do_other_stuff()
>
> ###################
> # Threads
>
> @thread.start_new:
> def &():
>       do_some_work()
>
>
> Best regards,
> Jan Kaliszewski