On 9/4/07, Giacomo Cerrai <[EMAIL PROTECTED]> wrote:
> A typical case I feel the need for that is when you have a hierarchy of
> classes where you deal with a lot of data fields and you name them with
> class data members:
>
> our FIELDNAME1 = 'field1';
> our FIELDNAME2 = 'field2';
> ...
> our FIELDNAMEn = 'fieldn';
>
> and then you use them like this:
>
> foo({param1 => $val,
> fields => { $FIELDNAME1 => $val1,
> $FIELDNAME2 => $val2,
> ...
> $FIELDNAMEn => $valn,
> },
> });
> ...
> foreach my $field ($FIELD4, $FIELD2, ..., $FIELD10) {
> ...
>
> With accessor methods this would be considerably more verbose:
>
> foo({param => $val,
> fields => { $SomeClass->FIELDNAME1 => $val1,
> $SomeClass->FIELDNAME2 => $val2,
> ...
> $SomeClass->FIELDNAMEn => $valn,
> },
> });
> ...
> foreach my $field ($SomeClass->FIELD4, $SomeClass->FIELD2, ...,
> $SomeClass->FIELD10) {
> ...
>
> This becomes quickly unreadable and is not lazy.
> Furthermore every fieldname access is a method call which is too much
> overhead, especially when you have many fields to deal with.
If you put the field names into an array (or hash) then it becomes a lot easier.
our @FIELDNAMES = ( ... );
sub fieldnames { @FIELDNAMES };
my %fields;
my @names = $SomeClass->fieldnames();
@[EMAIL PROTECTED] = ($val1, $val2, ..., $valn);
foo({param1 => $val, fields => \%fields );
...
foreach my $field (@{$SomeClass->fieldnames()}) {
...
