[erlang-questions] eep-0012 (Extensions to comprehensions)

[Richard A. O'Keefe]

On 8 Aug 2008, at 2:08 pm, Darren New wrote:
>> Why will "many" people be bothered about this in Erlang,
>> when they apparently aren't bothered by it in C or Java
>> or Javascript?
>
> What makes you think they're not?  That they're not posting their  
> complaints about Java on an Erlang mailing list?

This is hardly the only mailing list I am on.
I was part of the comp.std.c community for many years.
Amongst all the issues raised, this never turned up.
>
>
>> Why is the "add one thing -> diff should be one line"
>> idea so important for changes to data constructors but
>> ONLY data constructors?
>
> Because data constructors often stand alone with no further change  
> needed (if you're doing data-driven programming), while changes to  
> method declarations require changes to all the callers as well?

Good point.

But let's remind ourselves what we are talking about.
If people write

	Files = [
	    'foo.bar',
	    'ick.ack'
	],
	...

then there is an issue which allowing trailing commas
would solve.  If, on the other hand, they write

	Files = [
	    'foo.bar',
	    'ick.ack'],
	...

then trailing commas are not going to help.  I count
about 5000 lines beginning with ] or } in the Erlang
sources; about one every 110 lines.  "C-like" rather
than "Lisp-like" seems to be a common convention for
records and -record declarations.

You haven't persuaded me, but those numbers have.

Erlang/OTP sources => people DO have lots of stuff
where trailing commas would be sensible.
Python => it doesn't spoil a nice language much to
do it.

Write an EEP and get it on record then.