Hello all!
Say you have a string:
KLEWREGREG-----REGREGEWD....-EWGREGERABCSHRE..----...XFGHWW

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(you can have only - and . between letters).
If I want to "expand" XFGHWW to get the 3 most close letters to it (HRE from EWGREGERABCSHRE), how could I write a pattern match?
My goal is to read the search backwards, that is I won't know beforehand the format of the total string... That means that the algorithm would be like:
1. Find substring XFGHWW
2. From its left, get 3 letters, that are now . or -
3. Print the new substring.

In reply to Pattern matching forwards/backwards??? by Anonymous Monk

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