@blueprintjs/core/dist/common/utils.d.ts

Core styles & components

/// <reference types="react" />
/** Returns whether `process.env.NODE_ENV` exists and equals `env`. */
export declare function isNodeEnv(env: string): boolean;
/** Returns whether the value is a function. Acts as a type guard. */
export declare function isFunction(value: any): value is Function;
/** Safely invoke the function with the given arguments, if it is indeed a function, and return its value. */
export declare function safeInvoke<R>(func: (() => R) | undefined): R;
export declare function safeInvoke<A, R>(func: ((arg1: A) => R) | undefined, arg1: A): R;
export declare function safeInvoke<A, B, R>(func: ((arg1: A, arg2: B) => R) | undefined, arg1: A, arg2: B): R;
export declare function safeInvoke<A, B, C, R>(func: ((arg1: A, arg2: B, arg3: C) => R) | undefined, arg1: A, arg2: B, arg3: C): R;
export declare function safeInvoke<A, B, C, D, R>(func: ((arg1: A, arg2: B, arg3: C, arg4: D) => R) | undefined, arg1: A, arg2: B, arg3: C, arg4: D): R;
export declare function elementIsOrContains(element: HTMLElement, testElement: HTMLElement): boolean;
/**
 * Returns the difference in length between two arrays. A `null` argument is considered an empty list.
 * The return value will be positive if `a` is longer than `b`, negative if the opposite is true,
 * and zero if their lengths are equal.
 */
export declare function arrayLengthCompare(a?: any[], b?: any[]): number;
/**
 * Returns true if the two numbers are within the given tolerance of each other.
 * This is useful to correct for floating point precision issues, less useful for integers.
 */
export declare function approxEqual(a: number, b: number, tolerance?: number): boolean;
/** Clamps the given number between min and max values. Returns value if within range, or closest bound. */
export declare function clamp(val: number, min: number, max: number): number;
/** Returns the number of decimal places in the given number. */
export declare function countDecimalPlaces(num: number): number;
/**
 * Throttle an event on an EventTarget by wrapping it in a `requestAnimationFrame` call.
 * Returns the event handler that was bound to given eventName so you can clean up after yourself.
 * @see https://developer.mozilla.org/en-US/docs/Web/Events/scroll
 */
export declare function throttleEvent(target: EventTarget, eventName: string, newEventName: string): (...args: any[]) => void;
export interface IThrottledReactEventOptions {
    preventDefault?: boolean;
}
/**
 * Throttle a callback by wrapping it in a `requestAnimationFrame` call. Returns the throttled
 * function.
 * @see https://www.html5rocks.com/en/tutorials/speed/animations/
 */
export declare function throttleReactEventCallback(callback: (event: React.SyntheticEvent<any>, ...otherArgs: any[]) => any, options?: IThrottledReactEventOptions): (...args: any[]) => void;