/**
 * `Number.isFinite` typed as a guard. Distinct from the global `isFinite()`
 * which coerces strings. Rejects `NaN` and ±Infinity.
 */
export declare function isFiniteNumber(x: unknown): x is number;
/** `Number.isInteger` typed as a guard. */
export declare function isInteger(x: unknown): x is number;
/**
 * Detect any of the JS typed-array views (Int8Array, Uint8Array, Float32Array,
 * etc.). Used at workbook-build boundaries where integration code may pass
 * numpy-style buffers — we accept them and iterate per-element rather than
 * refusing.
 */
export declare function isTypedArray(x: unknown): x is ArrayBufferView;