SPUG: Chained comparisons in Perl 6
Michael R. Wolf
MichaelRWolf at att.net
Mon Dec 22 18:52:17 PST 2008
At last week's meeting, there was a question about code like this:
if ($left < $middle < $right) { ... }
This is *not* legal Perl5 since the comparison operators are non-
associative (contrary to my side comment at the time). It will cause
a compile error in Perl5, and must be written as.
if ($left < $middle && $middle < $right) { ... }
For those who are interested in the nitty-gritty, search for "Chained
comparisons" in this Perl6 "Spec" (FKA "Synopsis") on "Perl Operators".
http://dev.perl.org/perl6/doc/design/syn/S03.html
Or "perldoc perlop" in Perl5.
Michael R. Wolf
All mammals learn by playing!
MichaelRWolf at att.net
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