List syntax (was: Re: help from the community?)

Douglas Philips dgou at
Tue Feb 6 22:17:03 EST 2007

On 2007 Feb 5, at 6:13 AM, Ulf Norell wrote:
> How about instead writing
> ( expr
> , expr
> , expr
> , expr
> , expr
> )
> The only extra work is when inserting an element at the beginning,  
> but you have the same problem in your example.

This a coding style issue. My point was that the syntax should not be  
inconsistently enforcing style, which it is, unless there is some  
payoff (which there doesn't seem to be).

I argue for making trailing commas optional everywhere that commas  
are used to separate items in a grouping (though the syntax  snippets  
I've posted before were only a few of those places, such as in tuples  
and lists).
Enforcing style is not always bad, and layout has some great things  
going for it. Layout is also flexible where
it doesn't need to be rigid. Given the experience with trailing  
commas in other languages, even some that support
a glimmer of functional programming :-), being rigid in this area  
doesn't seem to have a counterbalancing payoff...

I really like Brian Hulley's layout proposal:
because it means I can abandon commas and other syntax noise  
altogether and thus moot the issue.


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