difference between [a-z] and [\a-z]. The first one does not contain space ' ' in the range but the second one is matching for space ' '. Why??
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Barmar
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Kenny Omega
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Because `\a` = ASCII code 7 – Lucas Trzesniewski Jan 12 '18 at 10:46
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... and the characters from code 7 to character z (code 122) include the space and other characters. – Andy G Jan 12 '18 at 10:48
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1One of you should post that as an answer. – Barmar Jan 12 '18 at 10:48
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[a-z] matches a character from a to z
[\a-z] matches a character from \a to z
\a is not a. According to regex101.com \a matches the bell character (ASCII 7). I don't know what this character is but it looks like whitespace.
JackPRead
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\a is ASCII code 7 (bell). a-z would be the range of characters a through z.
So \a-z is the range of characters from \a to the character z (index 122) which includes the space character (and many others).
An ascii table confirms the range of characters covered.
If you wanted to allow for a backslash in addition to the characters a through z, then use [a-z\\] (the backslash needs to be escaped). [I moved it to the end as I find this version clearer.]
Andy G
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