in reply to Matching a truncated word

Clarification: It should match the truncated piece of the last word, but the string being searched contains stuff before that. E.g. 
$text= "This sentence ends in foob";  # truncated from "...foobar"
$text =~ /foobar$/;
$text =~ /fooba$/;
$text =~ /foob$/;
... etc. ...

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Re^2: Matching a truncated word
by tadman (Prior) on Aug 01, 2001 at 00:28 UTC
    Hopefully this isn't too obfuscated. I've tried to restrain myself here. The trunc_match function creates a regular expression for any given input string, and should handle wierd stuff to by virtue of the qr() operator. 
    sub trunc_match
{
        my ($what) = @_;
        my @bits;

        for (1..length $what)
        {
                push (@bits,$what);
                chop $what;
        }

        return '('.join ('|', map { quotemeta($_) } @bits).')$';
}

my $rx = trunc_match ("foobar");

$_ = "This sentence ends in foob";

if (/$rx/)
{
        print "Truncated, ends in '$1'\n";
}

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    The format of the regex is something like:
    (foobar|fooba|foob|foo|fo|f)$
    So you get whatever you're looking for in $1, or the returned array if you're brave enough to use /g.

    Update:
    For some reason, I had confused qr with quotemeta, and so I am updating the code here to be more sensible in that regard. Thanks, once again, Hofmator.
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      That's an interesting use of qr// to escape out the individual parts, instead of using logic involving \Q..\E. I like the idea, since it avoids the confusion of escape chars in strings vs. in regex, and multiple levels of escaping. I'll be sure to remember that.

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