Trying to get the intuition behind ^.{5}[^e]?$ for Order in regex golf -



Trying to get the intuition behind ^.{5}[^e]?$ for Order in regex golf -

i'm trying improve understanding of how question mark works in regular look

^.{5}[^e]?$

for regex golf game (https://regex.alf.nu/8).

right read 'given start of string, take 5 characters not followed e, end string. question mark reads if 5 characters not followed e or character, that's end of string.

i used regexper.com (http://www.regexper.com/#^.{5}[^e]%3f%24) help me understand don't think i'm understanding ? correctly.

how ? work in comparing negative lookaheads, etc.

thank time.

that not followed e

not exactly. right description "that followed not-e" - that's negated character class does. , such not-e create sense optional.

what read "not followed by" negative lookahead, , indeed if optional don't create sense (as in: can omitted).

regex

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