Grrr! I wish they wouldn't do that.
Anticipating more ante upping, with deeply nested brace/bracket combos and wanting to capture a nested (but not an isolated) '{}' or '[]', e.g. '{ {} }', here's (maybe) a bit of a cheat:
#!/usr/bin/env perl -l
use strict;
use warnings;
my ($brace_re, $bracket_re);
$brace_re = qr< { (?: [^{}]++ | (??{ $brace_re }) )* } >x;
$bracket_re = qr< \[ (?: [^\[\]]++ | (??{ $bracket_re }) )* \] >x;
my $re = qr< ( $brace_re | $bracket_re ) >x;
while (<DATA>) {
print;
while (/$re/g) {
print "MATCH = $1" if length $1 > 2;
}
print '-' x 60;
}
__DATA__
...?[](...$[] = [ USER_ENTITY_NAME ], text${} = { this is a test })...
a[] = [ this is a [ test ] { test2 } ]
a{} = { this is a { test } [ test2 ] }
{ a { b [ {}c{} ] d } e } = [ f [ g { []h[] } i ] j ]
{}[]{ {}[] }[]{} - []{}[ []{} ]{}[]
Output:
...?[](...$[] = [ USER_ENTITY_NAME ], text${} = { this is a test })...
MATCH = [ USER_ENTITY_NAME ]
MATCH = { this is a test }
------------------------------------------------------------
a[] = [ this is a [ test ] { test2 } ]
MATCH = [ this is a [ test ] { test2 } ]
------------------------------------------------------------
a{} = { this is a { test } [ test2 ] }
MATCH = { this is a { test } [ test2 ] }
------------------------------------------------------------
{ a { b [ {}c{} ] d } e } = [ f [ g { []h[] } i ] j ]
MATCH = { a { b [ {}c{} ] d } e }
MATCH = [ f [ g { []h[] } i ] j ]
------------------------------------------------------------
{}[]{ {}[] }[]{} - []{}[ []{} ]{}[]
MATCH = { {}[] }
MATCH = [ []{} ]
------------------------------------------------------------
Update:
For Perl v5.8, you'll need to change [...]++ to (?> [...]+ ) (the '++' appeared in v5.10) and qr<...> delimiters will need to be something else, e.g. qr!...!.
The '(??{ $re })' construct has been around since at least v5.8.8.
Here's the perlre doco for 5.8.8 and 5.10.0.
