36 lines
986 B
JavaScript
36 lines
986 B
JavaScript
module.exports = Phrase;
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// Adds `reverse` to all strings.
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String.prototype.reverse = function() {
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return Array.from(this).reverse().join("");
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}
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// Defines a Phrase object.
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function Phrase(content) {
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this.content = content;
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// Returns content processed for palindrome testing.
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this.processedContent = function processedContent() {
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return this.letters().toLowerCase();
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}
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// Returns the letters in the content.
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// For example:
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// new Phrase("Hello, world!").letters() === "Helloworld"
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this.letters = function letters() {
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let theLetters = [];
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const letterRegex = /[a-z]/i;
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Array.from(this.content).forEach(function(character) {
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if (character.match(letterRegex)) {
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theLetters.push(character);
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}
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});
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return theLetters.join("");
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}
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// Returns true if the phrase is a palindrome, false otherwise.
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this.palindrome = function palindrome() {
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return this.processedContent() === this.processedContent().reverse();
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}
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}
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