map { } and "next"

[youradds]

Hi,

I've got a bit of a problem :/

Basically, I'm looping a hashref with;

map {
 ...
} keys %$var;

However, if you do;

map {
 .. do something
  if (something) { 
    next; 
  }
} keys %$var;

Basically, I just need to know what the map{} equivilant of "next" is?

TIA

Andy

 

[ishnid]

There isn't one! Normally you'd use grep to filter out the elements you don't want, and then use map to alter them.

You seem to be using map in a void context there: can you post the actual code and perhaps we can suggest an alternative?

 

[youradds]

Hi,

Thats what I thought :/

Well, here is some actual example code;

    map {
        my ($username,$site) = split /--/, $_;
        if ($seen->{$_} > 1) {

        print "\n";
        print "===" x 20;
        print "\n";

       if (ref $user ne "HASH") {
         next;
       }
       if (!$user->{Username}) {
         next;
       }

#  .. more stuff here
   } keys %$users;

...and I've also tried;

    LOOPSUBS: map {
        my ($username,$site) = split /--/, $_;
        if ($seen->{$_} > 1) {

        print "\n";
        print "===" x 20;
        print "\n";

       if (ref $user ne "HASH") {
         next LOOPSUBS;
       }
       if (!$user->{Username}) {
         next LOOPSUBS;
       }

#  .. more stuff here
   } keys %$users;

TIA

Andy

 

[ishnid]

Using map in a void context doesn't really make logical sense, since the purpose of map is to transform list elements in some way. Here, you can just use a for() loop, like so:

for ( keys %$users ) {
        my ($username,$site) = split /--/, $_;
        if ($seen->{$_} > 1) {

        print "\n";
        print "===" x 20;
        print "\n";

       if (ref $user ne "HASH") {
         next;
       }
       if (!$user->{Username}) {
         next;
       }

#  .. more stuff here
   } 
[code]

 

[youradds]

Hi,

Yeah, its a bit of a funny old script <G> It spans between 5 sites, and due to this, the "key" in the hashref is the value of the site, user and ID.

I've changed it to a for() and its working great now.. thanks =)

Cheers

Andy