I have a string that begins with a variable sequence of characters, which is followed by a constant string that can be used as a unique anchor. I want to strip off the variable stuff at the beginning so that it begins with the anchor. For example, given this:

my $s = 'variable chars anchor want this';
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I want to end with this:

$s = 'anchor want this';
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I can think of several ways to approach this, but I do not know which might be considered better than others from the standpoint of style or efficiency (not just benchmarking, but also including potential for backtracking). These approaches include:

• Capture the wanted portion

if( $s =~ m/^.*?(anchor.*)$/ ){ $s = $1; }
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• Capture and strip the variable portion

if( $s =~ m/^(.*?)anchor/ ){ my $bad = $1; $s =~ s/$bad//; }
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$s =~ s/^.*?anchor/anchor/;
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• Silly constructs

e.g., loops that utilize reverse, chop, split, ...
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All of these employ .* (except for the silly constructs, which are left as an exercise for the reader), but I am trying to avoid that idiom by thinking more carefully about my regexen (Death to Dot Star!). I suspect a better regex might be something like a negated character class, but for a group: "match everything from the start of the string that does not match the sequence of characters anchor".

How would you do this, and why?

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