NAME
    Syntax::Keyword::Val - Provides a readonly variant of 'my' called 'val'

WARNING
    While I do have serious intentions for this module in the future, it is
    definitely a *toy* as written now. At this stage, it serves better as a
    simple example of using Keyword::Simple.

DESCRIPTION
    Simply use this module, then place the "val" keyword where you'd
    normally use "my" for a read-only variant.

     use Syntax::Keyword::Val;

     val $foo = "bar";
     $foo = 123;        # ERROR

     val $foo = {a => 123, b => 456};
     $foo->{a}   = 666;       # ERROR
     $foo->{xyz} = "xyzzy";   # ERROR
     delete $foo->{b};        # ERROR

    The implementation uses Data::Lock, which itself uses the very fast
    internal SV flag to enforce the read-only status, so there should be no
    runtime penalty for using it.

BUGS
    Bugs and missing features aplenty. To start, due to the hacky
    implementation using Keyword::Simple (which is great, but quite
    limited), the "val" keyword currently only works for standalone
    declarations, i.e. statements that would normally begin with "my".
    Statements like this will not work:

     # Doesn't work, will generate a syntax error
     open val $fh, '<', $filename;

    Only scalars and references can be declared as "val". Attempting to
    declare a list or hash as a val will make it a normal variable (and
    issue a warning)

     # Issues a warning (assuming 'use warnings' is in effect)
     val @foo = qw(foo bar baz);

    Finally, "val" only applies to the first variable in a group, and the
    rest are read-write as normal.

     # Issues a warning (assuming 'use warnings' is in effect)
     val ($foo, $bar) = @baz;

AUTHOR
    Chuck Adams <cja987@gmail.com>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2013 by Chuck Adams

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.

