Unfortunately, [the substitution] also removes any leading whitespace from the remainder of the string

Oops, I completely missed that. But adding a trailing

  $_[0] =~ s/^\s+//;

[download]
to $_consume() is enough to fix that.

Unfortunately, I cannot flatten the nesting in quite the way you have as the $pos ($length as you have it) will also be undefined if $first is undefined.

Both your original code and dragonchild's refactor contradict this - both use the returned $pos1 ($pos) unaltered when $first is undefined.

For now, the magic problem doesn't arise as $str is just a string (generated wholey within the outer layers of my code and will not have any magic attached)

As I remember it, the principle (and most embarrassing) time that it becomes a problem is when the parameter is tainted.

Hugo

In reply to Re^3: Refactoring challenge. by hv
in thread Refactoring challenge. by BrowserUk

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