Regular Expressions 101

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/
^\[([\w\s\d]+)\]\((https?:\/\/[\w\d.\/?=#]+)\)$
/
gm
^ asserts position at start of a line
\[ matches the character [ with index 9110 (5B16 or 1338) literally (case sensitive)
1st Capturing Group
([\w\s\d]+)
Match a single character present in the list below
[\w\s\d]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\w matches any word character (equivalent to [a-zA-Z0-9_])
\s matches any whitespace character (equivalent to [\r\n\t\f\v ])
\d matches a digit (equivalent to [0-9])
\] matches the character ] with index 9310 (5D16 or 1358) literally (case sensitive)
\( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
2nd Capturing Group
(https?:\/\/[\w\d.\/?=#]+)
http
matches the characters http literally (case sensitive)
s
matches the character s with index 11510 (7316 or 1638) literally (case sensitive)
: matches the character : with index 5810 (3A16 or 728) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
Match a single character present in the list below
[\w\d.\/?=#]
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
\w matches any word character (equivalent to [a-zA-Z0-9_])
\d matches a digit (equivalent to [0-9])
. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\/ matches the character / with index 4710 (2F16 or 578) literally (case sensitive)
?=#
matches a single character in the list ?=# (case sensitive)
\) matches the character ) with index 4110 (2916 or 518) literally (case sensitive)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String