Regular Expressions 101

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/
.+(?=)
/
gmu
.
matches any character, including unicode (except for line terminators)
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
matches the character with index 1239910 (306F16 or 301578) literally (case sensitive)
Positive Lookahead
(?=)
Assert that the Regex below matches
matches the character with index 1239510 (306B16 or 301538) 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)
u modifier: unicode. Pattern strings are treated as UTF-16. Also causes escape sequences to match unicode characters
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gmu

Test String

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