Regex pattern match - Printable Version

Regex pattern match - Printable Version

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Regex pattern match - WJSwan - Feb-06-2023

I am trying to match all characters between "\x" and "\xk" for instance: in the string "\x - \xo 2:2 \xk".

I set my pattern as:

pattern = "\\x.+\\xk"
replaceWith = "<b>"
irec=re.sub(pattern, replaceWith, irec)

However, this gives me an error in my replace. I also tried:

pattern = r"\x.+\xk"
replaceWith = "<b>"
irec=re.sub(pattern, replaceWith, irec)

But this gives same error: re.error: incomplete escape \x at position 0

RE: Regex pattern match - deanhystad - Feb-06-2023

This is the double whammy. "\" is the start of an escape sequence for a str literal and it is the start of a special sequence in a regex pattern. Use one of these:

pattern = r"\\x.+\\xk"
pattern = "\\\\x.+\\\\xk"

You need the "\\x" to tell Python that the "\x" is not the start of a hex number. This makes the python str look like "\x.+\xk". But "\" in a pattern string is also meaningful, so we need another backslash to tell regex that we really want the characters '\' and 'x'.

RE: Regex pattern match - WJSwan - Feb-07-2023

Thank you!