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why "aab" matchs "ab" when using reglar expression ?

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Top Forums Shell Programming and Scripting why "aab" matchs "ab" when using reglar expression ?
# 8  
Old 08-21-2011
Althought 'ahamed101' already explained it. Execute:
Code:
$ man 7 regex

There is an explanation of how this kind of regular expression works.

Part of it says:
Quote:
A piece is an atom possibly followed by a single(!) '*', '+', '?', or bound. An atom followed by '*' matches a sequence of 0 or more matches of the atom. An atom followed by '+' matches a sequence of 1 or more matches of the atom. An atom followed by '?' matches a sequence of 0 or 1 matches of the atom.
Regards,
Birei
# 9  
Old 08-21-2011
Thanks all.
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