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0 pointsUehreka2y ago0 comments

> I don't need 12 different implementations for sorting on Vue/React/[insert spa framework of the month].

This feels like a bit of a strawman, since sorting is already in the standard library and there aren’t in fact popular sorting packages for each framework (that would in fact be ridiculous).

If you want to start a real debate though, bring up date/time pickers.

There are multiple date picker, time picker and datetime picker packages for each framework, and there are debates with good points on all sides about whether the browser-provided pickers are sufficient, or whether this is an area where a level of customization is needed and what that level is keeps changing as people discover new ways of designing date/time pickers and new use cases arise that require different tradeoffs. It’s both really frustrating but also kind of understandable.

0 comments

int_19h2y ago

There are still so many basic things that aren't in the JS stdlib, though. A good example is Map - if you need to use a tuple of two values as a key, you're SOL because there's no way to customize key comparisons. Hopefully we'll get https://tc39.es/proposal-record-tuple/ eventually, but meanwhile languages ranging from C++ to Java to Python have had some sensible way to do this for over 20 years now.

sroussey2y ago

It’s not key comparison issue:

const idx = [1,2] const m = new Map m.set(idx,"hi!") console.log(m.get(idx)) // outputs "hi!"

console.log(m.get([1,2]) // outputs undefined

That last line has created a new array object, and Map is made to be fast so checks equality by reference. Ah, which is what you to be able to change. I guess you would want to pass a new map a comparator function, so that it does a deep equal. That would be faster than what you would have to do now:

const idx2 = String([1,2]) m.set(idx2, "yo") console.log(m.get(idx2)) // yo console.log(m.get(String([1,2])) // yo

int_19h2y ago

That is precisely a key comparison issue. That is why I spoke about a tuple of two values; tuples by definition don't have a meaningful identity, so reference comparison is utterly meaningless for them.

Stringification is a very crude hack, and it doesn't even work in all cases - e.g. not if a part of your key still needs to be compared by reference. Say, it's a tuple of two object references, describing the association between those two objects.

Either way, the point is that this is really basic stuff that has been around in mainstream PLs for literally many decades now (you could do this in Smalltalk in 1980!).

moritzwarhier2y ago

There is a trivial way to have custom key comparisons: write a function that returns the key you want. You can implement equals() using some kind of serialization, or using a lookup table of references - whatever you want!

Of course, Records and Tuples would greatly simplify the process.

int_19h2y ago

Writing a key comparison function is not a problem. The problem is that Map does not have any way to use such a thing; it always compares using a predefined equality algorithm that is by-reference for all aggregate data types.

1 more reply

paulddraper2y ago

> since sorting is already in the standard library

Right. For example, to sort a list of numbers:

  [5, 14, 1, 2].sort()

Works great! No, wait, that's obviously wrong. Uh,

  [5, 14, 1, 2].sort((a, b) => a - b)

com2kid2y ago

> There are multiple date picker, time picker and datetime picker packages for each framework, and there are debates with good points on all sides about whether the browser-provided pickers are sufficient,

Safari (iOS and MacOS) still doesn't have full support for the date time picker, which is why there are so many alternatives.

j / k navigate · click thread line to collapse

0 pointsUehreka2y ago0 comments

> I don't need 12 different implementations for sorting on Vue/React/[insert spa framework of the month].

This feels like a bit of a strawman, since sorting is already in the standard library and there aren’t in fact popular sorting packages for each framework (that would in fact be ridiculous).

If you want to start a real debate though, bring up date/time pickers.

0 comments

int_19h2y ago

sroussey2y ago

It’s not key comparison issue:

const idx = [1,2] const m = new Map m.set(idx,"hi!") console.log(m.get(idx)) // outputs "hi!"

console.log(m.get([1,2]) // outputs undefined

const idx2 = String([1,2]) m.set(idx2, "yo") console.log(m.get(idx2)) // yo console.log(m.get(String([1,2])) // yo

int_19h2y ago

Either way, the point is that this is really basic stuff that has been around in mainstream PLs for literally many decades now (you could do this in Smalltalk in 1980!).

moritzwarhier2y ago

Of course, Records and Tuples would greatly simplify the process.

int_19h2y ago

1 more reply

paulddraper2y ago

> since sorting is already in the standard library

Right. For example, to sort a list of numbers:

  [5, 14, 1, 2].sort()

Works great! No, wait, that's obviously wrong. Uh,

  [5, 14, 1, 2].sort((a, b) => a - b)

com2kid2y ago

Safari (iOS and MacOS) still doesn't have full support for the date time picker, which is why there are so many alternatives.

j / k navigate · click thread line to collapse