NAME
    MooX::SetOnce - write-once attributes for Moo

SYNOPSIS
      package MyClass;
      use Moo;
      use MooX::SetOnce;

      has attr => ( is => 'rw', once => 1 );

DESCRIPTION
    MooX::SetOnce creates attributes that are not lazy and not set, but that
    cannot be altered once set.

    The logic is very simple: if you try to alter the value of an attribute
    with the SetOnce trait, either by accessor or writer, and the attribute
    has a value, it will throw an exception.

    If the attribute has a clearer, you may clear the attribute and set it
    again.

    If a Moose module extends or composes a module using MooX::SetOnce,
    MooseX::SetOnce will be loaded to provide the Moose implementation.

SEE ALSO
    MooseX::SetOnce

AUTHOR
    haarg - Graham Knop (cpan:HAARG) <haarg@haarg.org>

  CONTRIBUTORS
    None so far.

COPYRIGHT
    Copyright (c) 2013 the MooX::SetOnce "AUTHOR" and "CONTRIBUTORS" as
    listed above.

LICENSE
    This library is free software and may be distributed under the same
    terms as perl itself.