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in reply to Re: Replacing a specfied instance of a pattern in a string
in thread Replacing a specfied instance of a pattern in a string

Now, is there a way to do it with Regular Expression?

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Re^3: Replacing a specfied instance of a pattern in a string
by ikegami (Patriarch) on Jul 14, 2005 at 21:36 UTC
    my $str = 'Fsih my test variable is fsihd or is it gfsih or gfsih +d fsih'; # 1111 2222 3333 + 4444 my $substr = 'fsih'; my $regexp = qr/\Q$substr\E/; my $replace = 'fish'; my $instance = 3; # 3rd print("$str\n"); my $pre_count = $instance - 1; $str =~ s/((?:$regexp.*?){$pre_count})$regexp/$1$replace/; print("$str\n");

    You might have noticed both of these are case sensitive. Both can be made case-insensitive. The non-regexp version is most likely much faster. The regexp version can handle regexps instead of constant strings.