locutus/php/array/array_slice.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.array_slice = array_slice;
const is_int_ts_1 = require("../var/is_int.js");
function array_slice(arr, offst, lgth, preserveKeys) {
    //      discuss at: https://locutus.io/php/array_slice/
    // parity verified: PHP 8.3
    //     original by: Brett Zamir (https://brett-zamir.me)
    //        input by: Brett Zamir (https://brett-zamir.me)
    //     bugfixed by: Kevin van Zonneveld (https://kvz.io)
    //          note 1: Relies on is_int because !isNaN accepts floats
    //       example 1: array_slice(["a", "b", "c", "d", "e"], 2, -1)
    //       returns 1: [ 'c', 'd' ]
    //       example 2: array_slice(["a", "b", "c", "d", "e"], 2, -1, true)
    //       returns 2: {2: 'c', 3: 'd'}
    const preserve = preserveKeys === true;
    let result;
    if (Array.isArray(arr) && !(preserve && offst !== 0)) {
        if (lgth === undefined) {
            result = arr.slice(offst);
        }
        else if (lgth >= 0) {
            result = arr.slice(offst, offst + lgth);
        }
        else {
            result = arr.slice(offst, lgth);
        }
    }
    else {
        const sourceAssoc = {};
        let sourceLength = 0;
        if (Array.isArray(arr)) {
            for (let index = 0; index < arr.length; index += 1) {
                sourceLength += 1;
                sourceAssoc[String(index)] = arr[index];
            }
        }
        else {
            for (const key in arr) {
                sourceLength += 1;
                sourceAssoc[key] = arr[key];
            }
        }
        const normalizedOffset = offst < 0 ? sourceLength + offst : offst;
        const resolvedLength = lgth === undefined ? sourceLength : lgth < 0 ? sourceLength + lgth - normalizedOffset : lgth;
        const sliced = {};
        let started = false;
        let sourceIndex = -1;
        let collected = 0;
        let sequentialKey = 0;
        for (const key in sourceAssoc) {
            sourceIndex += 1;
            if (collected >= resolvedLength) {
                break;
            }
            if (sourceIndex === normalizedOffset) {
                started = true;
            }
            if (!started) {
                continue;
            }
            collected += 1;
            if ((0, is_int_ts_1.is_int)(key) && !preserve) {
                sliced[String(sequentialKey)] = sourceAssoc[key];
                sequentialKey += 1;
            }
            else {
                sliced[key] = sourceAssoc[key];
            }
        }
        result = sliced;
    }
    return result;
}