Carl Mäsak wrote: > Yesterday I got bitten by the fact that currently in Rakudo, $/ > doesn't copy content from the matched string, but instead trusts that > it stays in the matched string and doesn't change. > > Is this the intended behaviour, or should $/ keep a copy the string > contents? As the following examples show, Im hoping for the latter. > > # should $/ really keep ties to $s like this? > <masak> rakudo: my $s = "hello"; $s ~~ /hello/; $s = "goodbye"; say $/ > <p6eval> rakudo 29834: OUTPUT[goodb]
I'm pretty sure it's a bug in rakudo. The "live tie" you mentioned in the subject should only be present if the :rw modifier is given (but even then I think it should only work the other way round). > # I mean, it's not only unintuitive, it's dangerous, too > <masak> rakudo: my $s = "abcdefg"; $s ~~ /efg/; $s = "abc"; say $/ > <p6eval> rakudo 29834: OUTPUT[Cannot take substr outside > stringcurrent instr.: 'parrot;PGE::Match;text' pc 328 > (compilers/pge/PGE/Match.pir:220)] > > # this is how I discovered this behaviour. action at a distance! > <masak> rakudo: my $t = 'ABC'; $t ~~ /(A)B(C)/; $t = $0; my $u = $1; > <p6eval> rakudo 29834: OUTPUT[Cannot take substr outside > stringcurrent instr.: 'parrot;PGE::Match;text' pc 328 > (compilers/pge/PGE/Match.pir:220)] > > # the fact that there's such a method as .orig gives me some hope that > # the above is not the intended behaviour. however, as you see, $/.orig > # is not implemented in rakudo. > <masak> rakudo: my $s = "hello"; $s ~~ /ello/; say $/.orig > <p6eval> rakudo 29834: OUTPUT[Method 'orig' not found for invocant of > class 'PGE::Match'current instr.: '_block11' pc 60 (EVAL_14:24)] > > S05:2377: > > The currently defined methods are > > $/.from # the initial match position > $/.to # the final match position > $/.chars # $/.to - $/.from > $/.orig # the original match string > $/.text # substr($/.orig, $/.from, $/.chars) $/.text seems to be a bit superfluous, because it's already available as ~$/ and $/.Str But that only as a side note. Cheers, Moritz -- Moritz Lenz http://moritz.faui2k3.org/ | http://perl-6.de/
