use v6-alpha;

role Math::Basic;

multi sub abs (; Num ?$x = $CALLER::_ )
    returns Num { ... }

multi sub exp (; Num ?$exponent = $CALLER::_, Num :$base )
    returns Num { ... }

multi sub log (; Num ?$x = $CALLER::_, Num :$base where { $base > 0 })
    returns Num { ... }

# mmm, curry!
&log10 := &log.assuming:base(10);

multi sub rand (; Num ?$x = 1, Num :$seed )
    returns Num { ... }

multi sub sign (; Num ?$x = $CALLER::_)
    returns Int { ( defined $x
            ? ( ($x > 0)
            ? 1
            : ($x < 0 ? -1 : 0 ) )
            : undef ) }

multi sub sqrt (; Num ?$x = $CALLER::_)
    returns Num { exp($x,0.5) }

1;