lo/docs/data/it-groupby.md

name, slug, sourceRef, category, subCategory, signatures, playUrl, variantHelpers, similarHelpers, position

name	slug	sourceRef	category	subCategory	signatures	playUrl	variantHelpers	similarHelpers	position
GroupBy	groupby	it/seq.go#L244	it	sequence	func GroupBy[T any, U comparable](collection iter.Seq[T], transform func(item T) U) map[U][]T	https://go.dev/play/p/2TnGK6-zs	it#sequence#groupby	core#slice#groupby it#sequence#partitionby it#sequence#groupbymap	80

Returns an object composed of keys generated from running each element of collection through a transform function. The value of each key is an array of elements responsible for generating the key.

Examples:

seq := func(yield func(string) bool) {
    _ = yield("apple")
    _ = yield("banana")
    _ = yield("apricot")
    _ = yield("blueberry")
}
grouped := it.GroupBy(seq, func(s string) string {
    return string(s[0]) // group by first letter
})
// grouped contains map with keys: "a": ["apple", "apricot"], "b": ["banana", "blueberry"]