super-utils-plus/dist/function/partial.js

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"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.partial = partial;
exports.partialRight = partialRight;
/**
 * Creates a function that invokes `func` with `partials` prepended to the arguments
 * it receives. This method is like `bind` except it does not alter the `this` binding.
 *
 * @param func - The function to partially apply arguments to
 * @param partials - The arguments to be partially applied
 * @returns The new partially applied function
 *
 * @example
 * ```ts
 * function greet(greeting, name) {
 *   return greeting + ' ' + name;
 * }
 *
 * const sayHelloTo = partial(greet, 'hello');
 * sayHelloTo('fred');
 * // => 'hello fred'
 * ```
 */
function partial(func, ...partials) {
    return function (...args) {
        // Create a copy of partials to avoid modifying the original array
        const argsWithPartials = [...partials];
        // Replace placeholder values with arguments
        let argIndex = 0;
        for (let i = 0; i < argsWithPartials.length; i++) {
            // If we encounter a placeholder, replace it with an argument
            if (argsWithPartials[i] === partial.placeholder) {
                if (argIndex < args.length) {
                    argsWithPartials[i] = args[argIndex++];
                }
            }
        }
        // Add any remaining arguments
        while (argIndex < args.length) {
            argsWithPartials.push(args[argIndex++]);
        }
        return func.apply(this, argsWithPartials);
    };
}
// Define a placeholder value
partial.placeholder = Symbol('partial.placeholder');
/**
 * This method is like `partial` except that partially applied arguments
 * are appended to the arguments it receives.
 *
 * @param func - The function to partially apply arguments to
 * @param partials - The arguments to be partially applied
 * @returns The new partially applied function
 *
 * @example
 * ```ts
 * function greet(greeting, name) {
 *   return greeting + ' ' + name;
 * }
 *
 * const greetFred = partialRight(greet, 'fred');
 * greetFred('hi');
 * // => 'hi fred'
 * ```
 */
function partialRight(func, ...partials) {
    return function (...args) {
        // Create a copy of partials to avoid modifying the original array
        const argsWithPartials = [...partials];
        // Replace placeholder values with arguments, from right to left
        let argIndex = args.length - 1;
        for (let i = argsWithPartials.length - 1; i >= 0; i--) {
            // If we encounter a placeholder, replace it with an argument
            if (argsWithPartials[i] === partialRight.placeholder) {
                if (argIndex >= 0) {
                    argsWithPartials[i] = args[argIndex--];
                }
            }
        }
        // Add any remaining arguments at the beginning
        const combinedArgs = [];
        for (let i = 0; i <= argIndex; i++) {
            combinedArgs.push(args[i]);
        }
        return func.apply(this, [...combinedArgs, ...argsWithPartials]);
    };
}
// Define a placeholder value
partialRight.placeholder = Symbol('partialRight.placeholder');