NAME

accessors::ro - create 'classic' read-only accessor methods in caller's package.

SYNOPSIS

  package Foo;
  use accessors::ro qw( foo bar baz );

  my $obj = bless { foo => 'read only? ' }, 'Foo';

  # values are read-only, so set is disabled:
  print "oh my!\n" if $obj->foo( "set?" ) eq 'read only? ';

  # if you really need to change the vars,
  # you must use direct-variable-access:
  $obj->{bar} = 'i need a drink ';
  $obj->{baz} = 'now';

  # always returns the current value:
  print $obj->foo, $obj->bar, $obj->baz, "!\n";

DESCRIPTION

The accessors::ro pragma lets you create simple classic read-only accessors at compile-time.

The generated methods look like this:

  sub foo {
      my $self = shift;
      return $self->{foo};
  }

They always return the current value, just like accessors::ro.

PERFORMANCE

There is little-to-no performace hit when using generated accessors; in fact there is usually a performance gain.

typically 5-15% faster than hard-coded accessors (like the above example).
typically 0-15% slower than optimized accessors (less readable).
typically a small performance hit at startup (accessors are created at compile-time).
uses the same anonymous sub to reduce memory consumption (sometimes by 80%).

See the benchmark tests included with this distribution for more details.

CAVEATS

Classes using blessed scalarrefs, arrayrefs, etc. are not supported for sake of simplicity. Only hashrefs are supported.

AUTHOR