binary selectors ambiguity and space
ncellier at ifrance.com
Sat May 13 00:10:48 UTC 2006
Sorry cannot find the thread which started this discussion,
but it seems i cannot have some binary selector with minus sign last.
For example, i can compile
Compiler evaluate: 'nil -+ nil'
Compiler evaluate: 'nil -/+ nil'
But i cannot compile
Compiler evaluate: 'nil +- nil'
Compiler evaluate: 'nil +/- nil'
I understand that eventually some expressions might be ambiguous like
1+-2 that can be interpreted as (1) + (-2) or (1) +- (2)
But such ambiguity could raise an error or warning,
and in most case, spaces will help disambiguating:
1+- 2 would be (1) +- (2)
1+ -2 would be (1) + (-2)
Funny, in current 3.9 spaces are ignored:
i have '1 +- 2' interpreted as (1) + (-2)
I cannot even write 1 +-+ 2, though no ambiguity lie there...
I guess all this is very squeak specific
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