Regular Expressions 101

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/
.+(?=\s-|\(|\?|\*)
/
gm
.
matches any character (except for line terminators)
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
Positive Lookahead
(?=\s-|\(|\?|\*)
Assert that the Regex below matches
1st Alternative
\s-
\s matches any whitespace character (equivalent to [\r\n\t\f\v \u00a0\u1680\u2000-\u200a\u2028\u2029\u202f\u205f\u3000\ufeff])
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
2nd Alternative
\(
\( matches the character ( with index 4010 (2816 or 508) literally (case sensitive)
3rd Alternative
\?
\? matches the character ? with index 6310 (3F16 or 778) literally (case sensitive)
4th Alternative
\*
\* matches the character * with index 4210 (2A16 or 528) 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.

Regular Expression
No Match

/
/
gm

Test String

Code Generator

Generated Code

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Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions