Im currently working on a modul for a crypto tool and Im having some problems. The modul is supposed to be able to match word by the use of a mask consisting of letters. For exemple should the mask abb match the words t ree and s upp ose.
So far I have written a parser that generates a regex patttern. The mask abba becomes the pattern (\w)(\w)\2\1. So far so good.
The problem arises when I use a mask similar to the following, abcd. This mask matches cats but also room because of the fact that \w matches any letter. In other words, I want that two letters in the mask are two different letters in the match. For exemple cant both b and c match o (see the room example).
I have tried to solve the problem by using this pattern instead, (\w)([^\1])([^\1\2])([^\1\2\3]). The problem is that regex doesnt seem to be able to replace the \1 with the first group ((\w)) when the \1 is inside [].
Is there any to solve this problem? I havent worked much with regex so its possible that there are functions within regex which will solve the problem.
So far I have written a parser that generates a regex patttern. The mask abba becomes the pattern (\w)(\w)\2\1. So far so good.
The problem arises when I use a mask similar to the following, abcd. This mask matches cats but also room because of the fact that \w matches any letter. In other words, I want that two letters in the mask are two different letters in the match. For exemple cant both b and c match o (see the room example).
I have tried to solve the problem by using this pattern instead, (\w)([^\1])([^\1\2])([^\1\2\3]). The problem is that regex doesnt seem to be able to replace the \1 with the first group ((\w)) when the \1 is inside [].
Is there any to solve this problem? I havent worked much with regex so its possible that there are functions within regex which will solve the problem.