[erlang-questions] erlang *****
Andras Georgy Bekes
Mon Mar 17 16:02:31 CET 2008
> But now consider
So matching this pattern must involve backtracking. Awww.
> You could hack around this by requiring that if a head variable is
> bound in a disjunctive pattern it is not matched by any other head
The problem does exist in a single pattern:
We could of course generalise the above restriction, but it doesn't make
But what are the real problems with the search for the right match with
backtracking? If the programmer has written that silly pattern, he/she
should be aware that it might not be very fast. Are there consequences
other than the match being slow?
> I note that my abstract pattern proposal *already* gives you
> disjunctive patterns, BUT in such a way that the disjunctions can't
> interact like this.
Could you give some reference?
I've searched for "abstract pattern" in the archives and found a few
mail, but not your paper.
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