http://qs1969.pair.com?node_id=557918


in reply to Re: adding an IF to a push
in thread adding an IF to a push

Although Zaxo is right, I imagine it'd be okay, too, if the condtional statements were wrapped in a sub{} and you just check the return value in the proposed if().


"Age is nothing more than an inaccurate number bestowed upon us at birth as just another means for others to judge and classify us"

sulfericacid

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Re^3: adding an IF to a push
by ikegami (Patriarch) on Jun 28, 2006 at 04:40 UTC
    You mean like the following?
    push @array, $string =~ m#stuff#g if sub { my $img = get($image); my ($height, $width) = imgsize(\$img); $height < $max_h and $width < $max_w; }->();

    Zaxo's do is more direct and has less overhead, but why not just use the following:

    my $img = get($image); my ($height, $width) = imgsize(\$img); push @array, $string =~ m#stuff#g if $height < $max_h and $width < $max_w;

    You can wrap the whole thing in curlies if you want to limit the scope of $img, $height and $width.

      Actually I was going to go out on a lim and try
      my $num = 5; if (\&add($num) { .. } sub add { my $shift = shift; my $num2 = 10; my $sum = $num1 + $num2; if ($sum == "15") { return 1; } else { return 0; } }
      But after playing through numerous attempts, I couldn't pull it off. I just figured you should be able to test the return of a sub this way, though I've never thought of trying it until now.


      "Age is nothing more than an inaccurate number bestowed upon us at birth as just another means for others to judge and classify us"

      sulfericacid

        Change
        if (\%add($num) { .. }
        to
        if (add($num)) { .. }

        In context, it would actually be:

        sub is_image_size_ok { my ($image) = @_; my $img = get($image); my ($height, $width) = imgsize(\$img); return $height < $max_h and $width < $max_w; } push @array, $string =~ m#stuff#g if is_image_size_ok($image);
      Hi. I have another question. The variable I test with is the data caught in the match ($1). I can't get $1 to hold a value. Is there another way to do this?
      push @found_images, $get_gal =~ m#http://images\.imagefap\.com/imag +es/thumb/\d+/\d+/\d+\.jpg#g if do { my $image = get($1); print "found $1<br>"; my ($height, $width) = imgsize(\$image); $height < $max_height and $width < $max_width; };

        Two reasons:

        • You don't have any captures in your regexp, so $1 is never given a value.

        • The do is executed before the match. The match might not be executed at all, depending on the value returned by do.

        Fix:

        while ($get_gal =~ m#(http://{...}.jpg)#g) { my $image = get($1); my ($height, $width) = imgsize(\$image); push @found_images, $1 if $height <= $max_height and $width <= $max_width; }

        Bunch of alternative styles:

        You have to insert parens into your m## operation
        m#(http://images\.imagefap\.com/images/thumb/\d+/\d+/\d+\.jpg)#g
        or use $&
        # update: this won't work anyways - see previous post and followup push @found_images, $get_gal =~ m#http://images\.imagefap\.com/imag +es/thumb/\d+/\d+/\d+\.jpg#g if do { my $image = get($&); print "found $1<br>"; my ($height, $width) = imgsize(\$image); $height < $max_height and $width < $max_width; };
        at the expense of speed - see perlvar, section BUGS for that.
        _($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                                      /\_¯/(q    /
        ----------------------------  \__(m.====·.(_("always off the crowd"))."·
        ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}