UPDATE: I am an idiot, in my code I did a copy paste error and reinstantiated my nextline inside the while loop with...

while(...)
{
     my $nextline = <IN>
     .....
}

[download]

That I am assuming was scoped within the while loop. So I guess if a mod could delete this, that would be super.

So I am trying to write some code to skip over empty lines in some rather large files, so I am trying...

my $nextline = <IN>;
while($nextline eq '')
{
      $nextline = <IN>;
      print"Nextline is empty\n";
}

[download]

If I am reading a file with EMPTY LINE,EMPTY LINE,EMPTY LINE,EMPTY LINE,4,5 and 6 each on a new line.

my print statements will be

Nextline is

Nextline is

Nextline is

Nextline is

Nextline is 4 # SHOULD EXIT THE WHILE LOOP

Nextline is 5 # BUT STILL IN IT

Nextline is 6 # STILL IN IT!

So my nextline is getting updated correctly, but it doesn't seem that the condition for the while loop is using it?

I know my logic is right since if I insert an if stmt that checks the same conditon...

...
if($nextline ne '')
{
     last;
}
...

[download]

It exits exactly how I want it to. So I am assuming conditions for while loops in perl are not behaving as one would normally expect.

In reply to While loop conditions in Perl by joemaniaci

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