catch in assignment

Robert Virding <>
Thu May 18 17:43:08 CEST 2000


Sean Hinde <> writes:
>All,
>
>Can anyone shed any light on the following behaviour:
>
>> A = catch 1.
>** 3: syntax error before: 'catch' **
>
>but
>
>> A = (catch 1).
>1
>
>It doesn't strike me as ambiguous to assign the result of a catch to a
>variable directly...

No, it isn't ambiguous.  The reason is that 'catch' is a prefix operator
which happens to have the same as '=' and '=' demands higher priority 
on the right.  You can write:

	catch A = 1.

Yes, this could be solved by a hack to the parser, but I never thought 
it was worth it.  The REAL way to solve it would be to change 'catch' 
so as not to be a prefix operator but to terminate with an 'end', but 
it was to late for that (which would save begin .. end):

	A = catch foo(X), bar(Y) end.

	Robert

-- 
Robert Virding                          Tel: +46 (0)8 692 22 12
Bluetail AB                             Email: 
Hantverkargatan 78                      WWW: http://www.bluetail.com/~rv
SE-112 38 Stockholm, SWEDEN
"Folk säger att jag inte bryr mig om någonting, men det skiter jag i".





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