Add __.valued wildcard

[mordv]

Hi! Thanks for this amazing library!

I often use {x: not(__.nullish)} pattern so I wonder can we add __.valued wildcard?

Which would look like this

const isValued = <T>(val?: T | null | undefined): val is T => val !== undefined && val !== null;

Happy to create PR, if you approve.

[gvergnaud]

Thanks for the suggestion, I'll consider it. In the meantime, since this can be implemented in user land with const valued = not(__.nullish), you can store this in your own codebase if you want to use this.

Update for TS-Pattern v4+:

const valued = P.not(P.nullish);