lang: funcs: Add epsilon checks to operator_polyfunc

[dbakong]

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Thanks for contributing to mgmt and welcome to the team!

[purpleidea]

@dbakong I think you're on the right track, the epsilon stuff should be done at the top and only once. As either a var or a const or an init() or a combination. See what works =D

[dbakong]

@purpleidea thanks, I moved it to the top.

[purpleidea]

I bet you can do even better! this computation still repeats each time.

[dbakong]

updated!

[purpleidea]

1. How can you simplify this?

2. It still runs for each use of the operator.

Can we do better?

[purpleidea]

Since you have this pattern:

math.Abs(input[0].Float()-input[1].Float()) > epsilon

Repeated very often, maybe it makes sense to have it be a helper function? Write this as a lambda, right under the epsilon definition. Secondly, check the > above. Is it that or do we want >= ?

Being precise about > vs >= is exactly the point of this problem. Review all the instances in your patch and clean up the other issues mentioned and resubmit!

I hope this is fun!
Thanks!

[purpleidea]

Should this be < instead of <= ?

[purpleidea]

I think the more elegant way to write this is to start off with something like:

result := false

And then in you condition you do: result = true

And at the end you put in the bool into the &BoolValue as result. (Similarly for other cases.)

[purpleidea]

> or >= ?

[purpleidea]

This is an unhelpful comment. Explain why this is the case, since the code is not intuitive.

[purpleidea]

@dbakong The epsilon helper doesn't make sense... Where is input coming from?

Put the patch back to the way it was before and get all the < > <= >= stuff perfect. LMK here when ready.

[dbakong]

@purpleidea I think I got the last missing operator update. Please review.