[Haskell-cafe] Comma in the front

Brian Hulley brianh at metamilk.com
Fri Jul 14 20:48:14 EDT 2006

Tim Docker wrote:
> These layouts feel a bit artificial to me. I am quite partial to
> python's
> list syntax - a trailing comma is optional. meaning you can write
>     [
>        a,
>        b,
>        c,
>     ]
> I'm surprised this approach isn't more widespread - Are there reasons
> why
> haskell syntax could not/should not be defined this way?

I think this would be confusing because it looks like a syntax error - the 
last element is missing. The advantage of just having comma as a separator 
is that it allows syntax errors to be detected, whereas making it optional 
would mean one less error is detected at compile time.

I'll take this opportunity to re-present my hyper-cool syntax proposal for 
lists ;-) :


No need for commas or a closing ] because we could just use layout!

Regards, Brian.
Logic empowers us and Love gives us purpose.
Yet still phantoms restless for eras long past,
congealed in the present in unthought forms,
strive mightily unseen to destroy us.


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