I'm getting some odd behavior in the chrome JavaScript console. How can this be possible?
start is 5
word is /[\w$]+/g
z is "z"
start && word.test(z)
=> false
(start && word.test(z))
=> true
start && (word.test(z))
=> false
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What is the regex for `word`? [Does it use the global flag?](https://stackoverflow.com/questions/1520800/why-does-a-regexp-with-global-flag-give-wrong-results) – VLAZ Jun 27 '20 at 20:23
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And what are values? – Vahid Alimohamadi Jun 27 '20 at 20:25
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edited to include extra info – Test Jun 27 '20 at 20:28
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1"*word is `/[\w$]+/g`*" - check the link I posted, in that case. Global regexes are stateful - running `.test` multiple times will produce different results. – VLAZ Jun 27 '20 at 20:31
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Ok, wow, that's really surprising. I'll answer it myself. – Test Jun 27 '20 at 20:33
1 Answers
1
This has to do with the RegExp global flag. Thanks for @VLAZ for spotting this.
Specifically, the global flag is stateful. The trouble is that the code was run multiple times across the same session but the state of the RegExp was changing.
It looks like the idea with a global stateful RegExp is that it never matches the same section of the string twice.
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