lookbehind

问题 I have this regex that uses forward and backward look-aheads: import re re.compile(\"<!inc\\((?=.*?\\)!>)|(?<=<!inc\\(.*?)\\)!>\") I\'m trying to port it from C# to Python but keep getting the error look-behind requires fixed-width pattern Is it possible to rewrite this in Python without losing meaning? The idea is for it to match something like <!inc(C:\\My Documents\\file.jpg)!> Update I\'m using the lookarounds to parse HTTP multipart text that I\'ve modified body = r\"\"\"------abc

问题 Is there a way to do negative and positive lookbehind in VBA regex? I want to not match if the string starts with \"A\", so I am currently doing ^A at the start of the pattern, then removing the first character of match(0). Obviously not the best method! I am using the regExp object. 回答1: VBA offers positive and negative lookaheads but rather inconsistently not lookbehind. The best example of using Regex with VBA that I have seen is this article by Patrick Matthews [Updated example using

问题 I have the following regex in a C# program, and have difficulties understanding it: (?<=#)[^#]+(?=#) I\'ll break it down to what I think I understood: (?<=#) a group, matching a hash. what\'s `?<=`? [^#]+ one or more non-hashes (used to achieve non-greediness) (?=#) another group, matching a hash. what\'s the `?=`? So the problem I have is the ?<= and ?< part. From reading MSDN, ?<name> is used for naming groups, but in this case the angle bracket is never closed. I couldn\'t find ?= in the