G'day Wcool,

You get the output: 

MATCH = [](EntityName$ = DERIVED_ATTRIBUTE_TABLE, FieldNames$[]

[download]

because

  1. Regex '\[' matches character in line: '['.
  2. Regex '.+?' matches at least one character (']') and then continues to match non-greedily (i.e. up to but not including the next ']'), that's '(EntityName$ = DERIVED_ATTRIBUTE_TABLE, FieldNames$['.
  3. Regex '\]' matches the ']' after that.

So, instead of matching any character one or more times non-greedily (i.e. '.+?'), what you really want is to match any character that isn't ']' one or more times greedily (i.e. '[^\]]+').

You get the ouput: 

MATCH = {} = { this is a test }

[download]

for much the same reasons. The fix is similar, changing '.+?' to '[^}]+'.

Also, unless you really want those extra captures, you can lose the two inner pairs of parentheses.

Here's my test:

#!/usr/bin/env perl -l

use strict;
use warnings;

my $line = 'EntityMappingFetchByName?[](EntityName$ = DERIVED_ATTRIBUT
+E_TABLE, FieldNames$[] = [ USER_ENTITY_NAME ], text${} = { this is a 
+test }), line 6';

my $re = qr< ( { [^}]+ } | \[ [^\]]+ \] ) >x;

print "MATCH = $1" while $line =~ /$re/g;

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Output:

MATCH = [ USER_ENTITY_NAME ]
MATCH = { this is a test }

[download]

-- Ken

In reply to Re: Regular expressions: Extracting certain text from a line by kcott
in thread Regular expressions: Extracting certain text from a line by Wcool

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