Re: [bug-gawk] Does gawk optimize length(row) in for-loop?

[arnold]

Peng Yu <address@hidden> wrote:

> Hi, I have the following two code snippets. The first one takes the
> length() out of the loop. I am wondering whether gawk does any
> optimization for case 2 so that length() is only called once. Or
> length() will be called multiple times in case 2?

In case 2, length() will be called each time around the loop. It
would be a mistake to "optimize" that out since row could be
changed within the loop itself.

Arnold

> # code snippet 1
>     nf = length(row)
>     for(i=dat_col; i<=nf; ++i) {
>       data[i] += row[i]
>     }
>
> # code snippet 2
>     for(i=dat_col; i<=length(row); ++i) {
>       data[i] += row[i]
>     }
>
> -- 
> Regards,
> Peng