$string =~ s/-L|L-/-/g;
$string =~ s/^L//;
$string =~ s/L$//;

##</code><code>##

$string =~ s/^L|(?<-)L|L(?=-)|L$//g;

##</code><code>##

# Does a bit more than stripping, but in an inconsequential fashion.
$string =~ s/^L|-L|L-|L$/-/g;