Operator overloading

[liquidev]

Once traits are implemented, it would make sense to make all the built-in operators dispatch to trait methods instead of magic bytecode. This does mean that for a few releases basic operations will take a performance hit, until we have an IR that would allow us to optimize bytecode better and do some rudimentary static type analysis to dispatch specialized bytecode instructions.

Here's a list of operators and their associated traits with methods, once that is finished:

Op	Trait	Method
infix ()	Call	call/n where n is the number of arguments in ()
prefix !	Not	not/0
prefix -	Negate	negate/0
infix *	Multiply	multiply/1
infix /	Divide	divide/1
infix +	Add	add/1
infix -	Subtract	subtract/1
infix ==	Equals	equals/1
infix !=	Equals	boolean NOT equals/1
infix <	Ordered	less/1
infix <=	Ordered	less_or_equal/1
infix >	Ordered	less/1 on the RHS
infix >=	Ordered	less_or_equal/1 on the RHS

. cannot be overloaded because it's magic for method lookups + calls.
= cannot be overloaded because it's magic for assignments.
and and or cannot be overloaded because they're magic for control flow.