So I've been reading up on perltoot and perltooc and have been trying to create my very first perl class..
It started like this:
package DataTable;
sub new {
my $class = shift;
my $self = {};
$self->{tablename} = undef;
$self->{columns} = [];
$self->{indices} = {};
bless($self, $class);
return $self;
}
sub tablename {
my $self = shift;
if (@_) { $self->{tablename} = shift; }
return $self->{tablename};
}
sub columns {
my $self = shift;
if (@_) { @{$self->{columns}} = @_; }
return @{$self->{columns}};
}
sub indices {
my $self = shift;
if (@_) { %{$self->{indices}} = @_; }
return %{$self->{indices}};
}
1;
But then, after having to add more array properties (datatypes, lengths, decimals, allownull, default) and copypasting the accessor subs, something itched.
So I revised it to..
package DataTable;
sub new {
my $class = shift;
my $self = {};
$self->{tablename} = undef;
$self->{columns} = [];
$self->{indices} = {};
$self->{datatypes} = [];
$self->{lengths} = [];
$self->{decimals} = [];
$self->{signed} = [];
$self->{allownull} = [];
$self->{default} = [];
$self->{usequote} = [];
}
bless($self, $class);
return $self;
}
# Accessor methods
sub ArrayAccessor {
my $arrayname = shift;
my $self = shift;
if (@_) { @{$self->{$arrayname}} = @_; }
return @{$self->{$arrayname}};
}
sub HashAccessor {
my $hashname = shift;
my $self = shift;
if (@_) { %{$self->{$hashname}} = @_; }
return %{$self->{$hashname}};
}
sub ScalarAccessor {
my $scalarname = shift;
my $self = shift;
if (@_) { $self->{$scalarname} = shift; }
return $self->{$scalarname};
}
sub tablename { return ScalarAccessor("tablename", @_); }
sub columns { return ArrayAccessor("columns", @_); }
sub indices { return HashAccessor("indices", @_); }
sub datatypes { return ArrayAccessor("datatypes", @_); }
sub lengths { return ArrayAccessor("lengths", @_); }
sub decimals { return ArrayAccessor("decimals", @_); }
sub signed { return ArrayAccessor("signed", @_); }
sub allownull { return ArrayAccessor("allownull", @_); }
sub default { return ArrayAccessor("default", @_); }
sub usequote { return ArrayAccessor("usequote", @_); }
1;
However, seeing the long list of accessor function calls, I still found the need for even more abstraction:
package DataTable;
sub new {
my $class = shift;
my $self = {};
$self->{tablename} = undef;
$self->{columns} = [];
$self->{indices} = {};
$self->{datatypes} = [];
$self->{lengths} = [];
$self->{decimals} = [];
$self->{signed} = [];
$self->{allownull} = [];
$self->{default} = [];
$self->{usequote} = [];
# Automatically create Accessor methods
foreach (keys(%{$self})) {
my ($type, $prefix, $suffix) = (ref($self->{$_}), "", "");
if ($type eq "ARRAY") {
$prefix = '@{';
$suffix = '}';
}
if ($type eq "HASH") {
$prefix = '%{';
$suffix = '}';
}
eval("sub $_ { " .
'my $self = shift;
if (@_) { ' . $prefix . '$self->{' . $_ . '}' . $suffix .
+' = @_; }
return ' . $prefix . '$self->{' . $_ . '}' . $suffix . ';
}');
}
bless($self, $class);
return $self;
}
1;
However, since this is my first attempt at OO-perl, I humbly submit this to the monks for comments :)
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