Actually it's trivial to still use an iterator-style for loop, you just have to pick something slightly different to iterate over.

my $target_word;
for my $idx ( 0..($#arglist-1) ) {
  if( $arglist[ $idx ] eq '-iL' ) {
    $target_word = $arglist[ $idx + 1 ];
    last;
  }
}
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