/** The largest delay browsers can represent reliably with setTimeout. */
export declare const MAX_TIMEOUT_MS=2147483647;
/** Returns a finite number or the supplied finite fallback. */
export declare function finiteNumber(value:number,fallback:number):number;
/** Returns a finite value clamped to the requested range, ordering inverted endpoints first. */
export declare function finiteRange(value:number,fallback:number,min?:number,max?:number):number;
/** Returns a finite integer, truncating fractional input and clamping it. */
export declare function finiteInteger(value:number,fallback:number,min?:number,max?:number):number;
/** Returns a finite, non-negative integer suitable for a count or index. */
export declare function finiteCount(value:number,fallback?:number,max?:number):number;
/** Returns a finite timer duration, capped at the browser timer ceiling. */
export declare function finiteDuration(value:number,fallback:number,min?:number,max?:number):number;
/**
* Returns `value`'s clamped position from `start` (0) to `end` (1) without
* overflowing when the finite endpoints span the full number range.
*/
export declare function finiteRatio(value:number,start:number,end:number,fallback?:number):number;
/**
* Interpolates between two finite endpoints without forming an overflowing
* `end - start` intermediate. The ratio is clamped to `[0, 1]`.
*/
export declare function finiteInterpolate(start:number,end:number,ratio:number):number;
/** Returns the arithmetic midpoint of two finite values without overflowing their difference. */
export declare function finiteMidpoint(start:number,end:number):number;
/** Adds finite values, saturating at the largest representable magnitude on overflow. */
export declare function finiteAdd(left:number,right:number,fallback?:number):number;
/** Whether `key` is one of the four arrow keys. */
export declare function isArrowKey(key:string):boolean;
/** Keys a slider-style control's onKeyDown acts on and onKeyUp commits after
*  — arrow keys plus the WAI-ARIA APG slider pattern's Home/End/PageUp/
*  PageDown shortcuts. */
export declare function isSliderKey(key:string):boolean;
/** Number of decimal places implied by `n`, including exponent notation.
*  `0.1` -> 1, `5` -> 0, and `1e-7` -> 7. Used to round a stepped value back
*  to the precision `n` itself implies, instead of leaving binary
*  floating-point noise in place. */
export declare function decimalPlaces(n:number):number;