Operations¹ on Collections with Ramda

Purpose	List	Object	Signature(s)
update/insert individual	update, assoc*, append, prepend	assoc*	Idx → a → {k: v} → {k: v}
insert range/collection	concat	merge*	[a] → [a] → [a];{k: v} → {k: v} → {k: v}
retrieve by key/index	nth, path, prop	prop, path	Idx → {a} → a
retrieve many by key/index		props
apply fn to single item	adjust, modify, modifyPath	modify2 3, modifyPath	Idx → (v → v) → {k: v} → {k: v}
apply fn to all items	map	map	(a → b) → [a] → [b]; (a → b) → {k: a} → {k: b}
apply each fn to individual	evolve	evolve3	{k: (v → v)} → {k: v} → {k: v}
apply each fn to each item	zipWith(call)		[a → b] → [a] → [b]
apply each fn to all items	ap		[a → b] → [a] → [b]
remove item	slice	dissoc*	String → {k: v} → {k: v}
remove range/collection	slice, difference, drop*	omit	Number → Number → [a] → [a], [a] → [a] → [a], [String] → {k: v} → {k: v}
subset by predicate	filter	filter	(a → boolean) → [a] → [a]; (a → boolean) → {k: a} → {k: a}

Footnotes

1. Except lenses ↩

2. modify(p, fn)≅evolve({[p]: fn}) ↩

3. Missing props are not evaluated. Rather use modify(p, fn)≅chain(assoc(p), o(fn, R.prop(p))) ↩ ↩²