Regular Expressions 101

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/
(?<=<).*?(?<name>\w+)=?(?<param>\w+)(?=>)
/
gm
Positive Lookbehind
(?<=<)
Assert that the Regex below matches
< matches the character < with index 6010 (3C16 or 748) literally (case sensitive)
.
matches any character (except for line terminators)
*? matches the previous token between zero and unlimited times, as few times as possible, expanding as needed (lazy)
Named Capture Group name
(?<name>\w+)
\w
matches any word character (equivalent to [a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
=
matches the character = with index 6110 (3D16 or 758) literally (case sensitive)
Named Capture Group param
(?<param>\w+)
\w
matches any word character (equivalent to [a-zA-Z0-9_])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Positive Lookahead
(?=>)
Assert that the Regex below matches
> matches the character > with index 6210 (3E16 or 768) literally (case sensitive)
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