Deriving a new Array from an existing Array:
['■','●','▲'].slice(1, 3) ⟼ ['●','▲']
['■','●','■'].filter(x => x==='■') ⟼ ['■','■']
['▲','●'].map(x => x+x) ⟼ ['▲▲','●●']
['▲','●'].flatMap(x => [x,x]) ⟼ ['▲','▲','●','●']
Eliezer Margareten emargareten
rauschma
/ array-cheat-sheet.md
Last active
June 20, 2026 20:20