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in reply to Re: How to avoid the duplication in a string
in thread How to avoid the duplication in a string

could you please explain what is the meaning for \1+ in perl
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Re: How to avoid the duplication in a string
by jonadab (Parson) on Oct 22, 2008 at 11:39 UTC
    could you please explain what is the meaning for \1+ in perl

    In regular expressions, backslashed numeric digits are references back to the preceding captures. So \1 refers to the same thing that was captured in the first set of parentheses, and \2 refers to the same thing that was captured in the second set, and so forth.

    As for the +, it modifies a backreference in exactly the same way it modifies any other atom in a regular expression.

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