concatArrays - API reference

Call Signature

function concatArrays<T>(
  first: readonly [T, T] | [T, ...T[]],
  second: readonly T[] | T[],
): readonly [T, T];

Concatenates two arrays, returning a new readonly array.

Returns a non-empty array when at least one input is non-empty.

concatArrays([1, 2], [3, 4]); // [1, 2, 3, 4]
concatArrays([], [1]); // [1] (non-empty)
concatArrays([1], []); // [1] (non-empty)

function concatArrays<T>(
  first: readonly T[] | T[],
  second: readonly [T, T] | [T, ...T[]],
): readonly [T, T];

Second non-empty.

function concatArrays<T>(
  first: readonly T[] | T[],
  second: readonly T[] | T[],
): readonly T[];

Both possibly empty.