Thanks. Not that I like this behavior but I think I'll have to live with it.

But if we are at it. My problem is that I have a function that returns two values when data is available to it and when no data remained it returns undef. 

sub recv_data{
    if(read_some_data){
        return($stuff1, $stuff2);
    } else {
        return;
    }
}

[download]
What I would like to do is to call this function in a while until all data is consumed. I tried to do this first by 
while(($x, $y) = recv_data){
    ...
}

[download]
which failed due to the above reasons (i.e., the while block always executed since ($x, $y) = recv_data always evaluates to true even if the function returns undef).

I still have the option to write 

while(1){
    my($x, $y) = recv_data;
    last unless defined $x;
    ...
}

[download]
but I fail to see this as elegant.

How to organize this code so that I obtain the required behavior in an elegant and readable way?

rg0now

In reply to Re^2: Can't understand function returning undefs by rg0now
in thread Can't understand function returning undefs by rg0now

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