p5pRT
commented
8 years ago From @nkh
Created by @nkh
Hi\,
based on perlre:
These special variables\, like the %+ hash and the numbered match variables ($1 \, $2 \, $3 \, etc.) are dynamically scoped until the end of the enclosing block or until the next successful match\, whichever comes first.
the following code parse a string which has the form {block1}* text* {block2} where block may be empty.
I use named capture (b1\, b2) to capture the blocks.
for each test case the following is display
test case
block1 text block2 text text
The problem can already be seen within the first iterations where $+{b1} should be undefined but has kept the previous value
adding an extra block fixes the problem
for (qw( ? {a} a{}? ?a{} ?{a} {a}?{b} {a}{b}{c} {a}{b}{c}{d} {a}bc{d} {a}bcd {?} { } {{} {a}{{{{{{b} {a}{{{{{{b {a}{{{{{{ {a}}}}}}{b} {a}}}}}}{b {a}}}}}}b} )) { #{{{ # perl bug fix print " $_\n" ; my $args = $_ ;
$args =~ s/^ (?'b1' (?:\{[^\{\}]*\}) ) //x ; print '>' . ($+{b1} // '') . "\n" ;
$args = reverse $args ;
$args =~ s/^ (?'b2' (?:\}[^\{\}]*\{) ) //x ; print '>' . reverse($+{b2} // '') . "\n" ;
my $t = reverse $args; print ">$t\n" ;
print "-----------------\n\n" ; #}}} }
Migrated from rt.perl.org#129771 (status was 'open')
Searchable as RT129771$