# --------------------------------------------------------------------------- #
# Num Role
# --------------------------------------------------------------------------- #
# - based partially on Haskell's Num class and Eiffel's NUMERIC
# --------------------------------------------------------------------------- #

^Num := ^Role.new({});

^Num.set_name('Ord');
^Num.set_version('0.0.1');
^Num.set_authority('url:pugscode.org');

^Num.set_roles(^Ord);

^Num.add_method('infix:<+>', -> $other {
	# ... addition
});

^Num.add_method('infix:<*>', -> $other {
	# ... multiplication
});

^Num.add_method('infix:</>', -> $other {
	# ... division
});

^Num.add_method('infix:<^>', -> $other {
	# ... exponent
});

^Num.add_method('infix:<%>', -> $other {
	# ... modulus
});

^Num.add_method('infix:<->', -> $other {
	# ... subtraction
	self.infix:<+>($other.prefix:<->())
});

^Num.add_method('prefix:<->', -> {
	# ... negation
	# 0 - x
	$?CLASS.new(0).infix:<->(self); 
});

# NOTE:
# This may not be right, and oversimplified
^Num.add_method('abs', -> {
	# (x < 0) ?? (x * -1) !! x
	self.infix:<<>($?CLASS.new(0))`if_else(
		-> { self },
		-> { self.infix:<*>($?CLASS.new(-1)) }
	);
});