File Coverage

blib/lib/Keyword/Value.pm

Criterion	Covered	Total	%
statement	33	49	67.3
branch	4	12	33.3
condition	3	9	33.3
subroutine	9	10	90.0
pod			n/a
total	49	80	61.2

########################################################################
# housekeeping
########################################################################
package Keyword::Value v0.1.2;
use v5.22;

use Keyword::Declare;

use Data::Lock      qw( dlock           );
use Carp            qw( carp croak      );

########################################################################
# package variables
########################################################################

our @CARP_NOT   = ( __PACKAGE__ );

# variable avoids having to export the sub into every caller's space.

our $const
= sub : lvalue
{
    state $verbose  = $ENV{ VERBOSE_KEYWORD_VALUE } // '';

    # lvalue delays dlock until after state sets its own magic flag.

    $_[0] = $_[1] if @_ > 1;

    $_[0] // carp "Fixing undefined value"
    if $verbose;

    dlock $_[0];

    # returns ref from stack to allow assignment via lvalue.

    $_[0]
};

########################################################################
# exported subs
########################################################################

sub import
{
    # defined inside of "import" this pushes the "value" keyword
    # into the caller's space.
    #
    # lock a variable (i.e., with a sigil).
    # lacking a leading variable, constify the entire expression.

    keyword value( Var $var, Expr $expr )
    {
        ( 0 > index "$var", '::' )
        ? "\$Keyword::Value::const->( my $var $expr )"
        : "\$Keyword::Value::const->(    $var $expr )"
    }

    keyword value ( Expr $expr )
    {{{
        $Keyword::Value::const->( <{$expr}> )
    }}}
}

# keep require happy
1
__END__