Why does this regex generate undefined entries?
356
Remove empty elements from an array in Javascript
114491
Reference to groups in a MySQL regex?
6448
Reference - What does this regex mean?
128484
How to filter string for unwanted characters using regex?
1685
Why does this Java regex cause "illegal escape character" errors?
28966
Is gcc 4.8 or earlier buggy about regular expressions?
122449
preg_match error Unknown modifier '{'
46974
What's the meaning of a number after a backslash in a regular expression?
61907
Right way to escape backslash [ \ ] in PHP regex?
146367
Umlauts in regexp matching (via locale?)
37735
How can I check for "undefined" in JavaScript?
102369
How to convert this PHP Regex to Javascript Regex?
41380
How to check if a given Regex is valid?
1805
Do Python regexes support something like Perl's \G?
63928
regex error - nothing to repeat
66916
Expressions containing globally undefined symbols inside a function where they are defined
12963
What is a non-capturing group in regular expressions?