API reference / @evolu/common / Assert / assertNonEmptyReadonlyArray

Variable: assertNonEmptyReadonlyArray()

const assertNonEmptyReadonlyArray: <T>(arr, message?) => asserts arr is readonly [T, ...T[]];

Defined in: packages/common/src/Assert.ts:87

Asserts that a readonly array is non-empty.

Ensures the provided readonly array has at least one element, helping TypeScript infer non-emptiness when this is logically guaranteed but not statically known.

Example

assertNonEmptyReadonlyArray([1, 2, 3]); // no-op
assertNonEmptyReadonlyArray([]); // throws Error

Type Parameters

Type Parameter
T

Parameters

ParameterType
arrReadonlyArray<T>
message?string

Returns

asserts arr is readonly [T, ...T[]]

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