Warning on sure-to-fail comparisons

[LenkyDev]

Emit warning on A = B where the user may unwittingly be comparing types which may never be equivalent.

Foo:int = 1
Bar:int = 2
Baz:float = 3.0

Example()<decides>:void = 
    # OK
    Foo = Bar
    
    # warning; common comparable subtype comparison
    Foo = Baz

this would however desire a way to silence the warning where it is a valid operation such as comparing class instances. In the further future I think comparing classes should be able to infer A:unique = B:unique as a trait and also avoid warning.

---

Mayapple

[sprintermax]

Yes! When the types are specific, should warn the user:

# Currently, comparisons that are guaranteed to never pass or fail does not have any warnings, this can causes bugs when refactoring code and changing types (common cases with int and float):

# Proposal: Add warnings to these cases, eg:

MyInt = MyFloat # Warning: This comparison works but will never succeed. Did you mean something else instead?
# and
MyInt <> MyFloat # Warning: This comparison works but will never fail. Did you mean something else instead?

Note: Basically the same warnings ALREADY exists for things such as impossible map lookups, just not for these comparisons:
(It is not "unlikely" tho, it is an fact, the message can be more precise than that hahaha)