Re: [Chicken-janitors] #1020: matchable: Add conversion pattern(s)

[Chicken Trac]

#1020: matchable: Add conversion pattern(s)
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  Reporter:  syn                |       Owner:  ashinn   
      Type:  enhancement        |      Status:  accepted 
  Priority:  not urgent at all  |   Milestone:  someday  
 Component:  extensions         |     Version:  4.8.x    
Resolution:                     |    Keywords:  matchable
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Comment(by syn):

 Right, implicit `and' makes for more convenient patterns but agreed,
 loss of portability is an issue, too. I'm also aware of the fact that
 -?> can be expressed by nesting ? (see the original ticket
 description) but I found it a bit verbose. Nice trick to use `values'
 for identity, by the way, I shall keep that one in mind. Anyhow, the
 use case I encountered for -?> is indeed what I gave as an
 example. This is especially handy when matching on
 (command-line-arguments) where some arguments are numbers. OTOH, maybe
 it is better to use = in that case, too, so that one can give a more
 meaningful error message rather than falling through to no matching
 pattern.

 I am much more in favor of a general extension mechanism, though, so
 that we can stop piling features on top :-) Do you have anything in
 mind how this could be accomplished? I'd gladly try my hand at
 implementing that!

-- 
Ticket URL: <http://bugs.call-cc.org/ticket/1020#comment:6>
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