Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Hi,

I'd like to get rid of above warning

on this piece of code (in the "if" line) :

sub get_attribute {
    my ( $self, $attribute ) = @_;
    if  ((exists(  $self->{ATTRIBUTES}  )) and  ( defined( ${ $self->{
+ATTRIBUTES} }{$attribute} ) )  ) {
        return ${ $self->{ATTRIBUTES} }{$attribute};
    }
    return undef;
}

[download]
How can I check if value exists before actually use it ?

Thanks in advance,

regards,

Bulek.

Replies are listed 'Best First'.
Re: Use of uninitialized value in hash element at
by wind (Priest) on Apr 05, 2011 at 20:55 UTC 
    sub get_attribute {
    my ( $self, $attribute ) = @_;
    
    return exists $self->{ATTRIBUTES} && exists $self->{ATTRIBUTES}{$a
+ttribute}
        ? $self->{ATTRIBUTES}{$attribute}
        : undef;
}

    [download]
[reply]
[d/l]
      sub get_attribute {
    my ( $self, $attribute ) = @_;
    
    return exists $self->{ATTRIBUTES}
        ? $self->{ATTRIBUTES}{$attribute}
        : undef;
}

      [download]
      will do the same, but if you don't mind to create $self->{ATTRIBUTES}, it maybe even shorter: 
      sub get_attribute {
    my ( $self, $attribute ) = @_;

    return $self->{ATTRIBUTES}{$attribute};
}

      [download]
[reply]
[d/l]
[select]
        Hi,

        thanks for responses... I've tried both solutions and I still get warnings :

        Use of uninitialized value in hash element at ....

        [download]


        line with return statement... Is there any chance to get rid of those warnings ?

        Thanks in advance, regards, Rob.
[reply]
[d/l]

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