Context

This is some groundwork to implement gas consumption in the typechecker.

The current type signature of typecheck function returns either true or false, but we have more than one mode of failure.

In particular, typechecker can run out of gas. Returning the same value for all modes of failure is obviously suboptimal.

In addition, using Result allows us to reduce boilerplate by using the ? operator.

This MR doesn't concern itself with improving errors themselves too much, this is left for further work. However, some obvious cases are added.

Manually testing the MR

cargo test

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Edited Sep 13, 2023 by Nikolay Yakimov