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JavaScript Snippet - random()

Have you ever had to pick a random value from an array or a range of numbers and wished there was a simple one-liner way of doing it? Me too! The following function will get that done for you:

Parameters

This function will accept zero, one or two arguments:

1. minOrArray {number | Array} - If a number is given and this is the only argument specified this will be used as the limit value while 0 will be used as the inclusive boundary for the range of numbers that can be returned. If a number is given and limit is not undefined or null this will be the the inclusive boundary for the range of numbers that can be returned. If an array is given a random value from this array will be returned.
2. limit {number | undefined | null} - If a number is given it will represent the exclusive boundary of the range of numbers from which a random number can be chosen.

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function getFullPath(dirOrFileEntry, callback) {
    chrome.fileSystem.getDisplayPath(dirOrFileEntry, callback);
}

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function readDirectory(dirEntry, callback) {
    dirEntry.createReader().readEntries(callback);
}

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function readFileAsText(fileEntry, callback) {
    fileEntry.file(function(file) {
        var reader = new FileReader();
        reader.onload = function(e) {
            callback(e.target.result);
        };
        reader.readAsText(file);
    });
}

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function writeFileAsText(fileEntry, text, opt_callback) {
    fileEntry.createWriter(function(writer) {
        writer.onwriteend = opt_callback;
        writer.write(new Blob([text], {type: 'text/plain'}));
    });
}

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/**
 * Recursively retrieves the contents of the specified DirectoryEntry.  All
 * entries are appended to an array assigned to the `entries` key of each
 * DirectoryEntry.
 * @param  {!DirectoryEntry} dirEntry  The DirectoryEntry representing the root
 *     directory for which all entries should be retrieved recursively.
 * @param  {function(Array.<DirectoryEntry,FileEntry>)} callback  Function
 *     called after all descendant directories have been traversed.
 */
function recurseDirectory(dirEntry, callback) {

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/**
 * Parses a string as if it was the contents of a CSV file.
 * @param {string} strCSV 
 * @param {?parseCSV__Options=} options
 * @return {*[][]}
 *   An array of arrays where each value comes from `strCSV`.
 */
function parseCSV(strCSV, options) {
  // Get and validate the delimiter.
  const delimiter = options?.delimiter ?? ',';

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// CSV contents generated in Excel.
var csv = "First Name,Last Name\nPat,O'Rielly\nSam,O'Brien\nJohn,Carter";

/**
 * Takes a string representation of a CSV and parses it into an array of arrays
 * or an array of objects (dictionaries).
 * @param  {string} strCSV
 *     String representation of a CSV.
 * @param  {boolean=} opt_headerRow
 *     Optional boolean defaulting to false which if set to true indicates that

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function inherit(C,S){var p='prototype';function O(){}O[p]=C[p];S[p]=new O}

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// Define a simple Being prototype with isLiving(), die(), and _living starting
// off as true.
function Being() {}
Being.prototype._living = true;
Being.prototype.isLiving = function() { return this._living; };
Being.prototype.die = function() { this._living = false; };

// Define a simple Person prototype which is constructed with a gender.
function Person(gender) { this._gender = gender; }