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JSAbrahams / mamba

🐍 The Mamba programming language, because we care about safety
MIT License
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WIP Also check None type in type checker #225

Closed JSAbrahams closed 2 years ago

JSAbrahams commented 2 years ago

Summary

Before, none was ignored partially by the unification stage. Now, none is just seen as any other type meaning that the same application logic is used to type check none types.

JSAbrahams commented 2 years ago

Still issues where constraints appear to be improperly generated, such that the left side is not the superset/supertype of the right side even when the input is correctly typed (according to the language specification).

I.e.: def f(a): Int? => 10

Is valid, as 10 is a Int and Int? is a supertype of Int, meaning that it should pass the type checking stage. Need to fix how some constraints are generated before merging. The same error appears also in simple arithmetic operations, not just functions, so not sure if this is an easy fix.