Incorrect typings for Heap#peek

[Jannis]

The documentation and TypeScript types for Heap#peek say that it always returns T. However, the current implementation returns T | undefined due to it's return this.values[0] implementation:

Code:

umbrella/packages/heaps/src/heap.ts

Lines 79 to 81 in 8fed74e

	peek() {
	return this.values[0];
	}

Docs: https://docs.thi.ng/umbrella/heaps/classes/_heap_.heap.html#peek

An empty Heap or DHeap would return undefined because emptyArray[0] is undefined.

My suggestion would be to either make peek return T | undefined (preferred due to its better developer ergonomics) or make it throw an exception if there are no values (less preferred), and potentially be more explicit in the documentation.

[earthlyreason]

Related: --noUncheckedIndexedAccess.

Haven't used that myself yet -- I imagine it's pretty breaky. But here, the unsafe signature is leaking into the API, so maybe something to consider.

[postspectacular]

Thanks @Jannis - I'd say the intention here definitely is T | undefined rather than throwing an error (same as Array.peek() contract). There're other parts/packages in umbrella where you will get an OutOfBoundsError, but in those case it's (IMHO) more justified & useful than doing so here. So we're on same page :)

@gavinpc-mindgrub thank you for that option, didn't know about that either, but will check it out!

[Jannis]

@postspectacular Awesome, thanks for the quick turnaround!

[postspectacular]

@Jannis Hah! Don't get used to it :) Will try to do a new release tomorrow...

[postspectacular]

Just pushed a new release! (changelog) 🎉