Static method naming

[acutmore]

With the new static based functions. I was wondering if there were alternatives to the groupBy name. Object.groupBy and Map.groupBy sounds a little like it operates on Object or Map as opposed to building them.

Background

The majority of static Object methods operate on an object argument:

• getOwnPropertyDescriptor
• getOwnPropertyDescriptors
• getOwnPropertyNames
• getOwnPropertySymbols
• hasOwn
• preventExtensions
• seal
• assign
• defineProperties
• defineProperty
• freeze
• getPrototypeOf
• setPrototypeOf
• isExtensible
• isFrozen
• isSealed
• keys
• entries
• values

The static Object methods that create an object, Object.create and Object.fromEntries, are in the minority but use words that strongly convey that a new value is being created.

Suggestions

Some alternatives we came up with at Bloomberg:

• Object.byGrouping
• Object.fromGrouping
• Object.groupFrom

Thoughts?

[ljharb]

There’s no clear precedent for this - Promise.all and friends produce a Promise, Object.fromEntries and Object.create produce an Object, Array.from produces an Array.

However, Object.keys/values/entries/getOwnPropertyDesceiptor etc operate on an Object.

[jridgewell]

I think having the name groupBy is important for recognizability (our own ecosystem precedent and from other languages). I don't think there's a clear pattern for naming factory methods.

[acutmore]

The recognisability of the name does sound very valuable. So like {_,Lodash,Ramda}.groupBy, in this situation the namespace should be seen as a general collection of utilities. And having Array.groupBy doesn't scale as nicely to having various different collection types.

[nickmccurdy]

How about fromGroups? It aligns with existing static methods like Array.fromAsync.

[bakkot]

@nickmccurdy This method is the opposite of that - your data is not grouped yet, and you want it to be.

[nickmccurdy]

I was thinking of it more from the mathematical perspective, where the callback is a functor mapping an ungrouped collection to a grouped collection. Though if the result is too arbitrary, maybe fromGrouping would be more clear.

[ljharb]

“fromX” means it’s an X already, and as you said, it’s ungrouped.

[Zachiah]

@nickmccurdy correct me if I'm wrong, but @ljharb I think what @nickmccurdy is suggesting is that groups is referring to the function that converts from "ungrouped" to "grouped". An expansion of the name could be: getGroupsFromGroups and when you consider the "more clear" version he provided: fromGrouping, this makes even more sense: getGroupsFromGrouping.

[ljharb]

Functions are verbs, so that function could be a "grouper" but wouldn't be "groups", a noun - and fromGrouper sounds like it's a fish :-)

[nickmccurdy]

I try to avoid putting get in function names as it's usually already obvious. Maybe just groups or grouped could work? Though I'm not sure if they'd have naming collisions.

[ljharb]

TC39 reaffirmed consensus today on the existing groupBy name.