Javascript Modules: Message Mixer

Simple JS scripts that mixes messages with different algorithms.

Message Mixer is a messaging service that allows you to perform an action on input text and display the output of that behavior to the console. For example, with the current functions defined in Message Mixer, you can:

• count the characters in a message
• capitalize the first character of words
• reverse a message’s words in place
• reversing characters in place
• replace the first occurrence of a string
• replace all occurrences of a string
• encode text by swapping certain characters for other characters

At present, Message Mixer runs as a program in a single file. This single file includes functions that define behavior as well as the output. Message Mixer knows that by extracting the functions into a module, logic can be reused in different parts of our application.

Let’s help Message Maker turn the program into a module!

Message.js

import {MessageMixer, countCharacter, capitalizeFirstCharacterOfWords, reverseWord, reverseAllWords, replaceFirstOccurence, replaceAllOccurrences, encode, palindrome, pigLatin} from './messageMixer';

function displayMessage() {
  console.log(countCharacter("What is the color of the sky?", "t"));
  console.log(capitalizeFirstCharacterOfWords("What is the color of the sky?"));
  console.log(reverseWord("What is the color of the sky?"));
  console.log(reverseAllWords("What is the color of the sky?"));
  console.log(replaceFirstOccurence("What is the color of the sky?", "sky", "water"));
  console.log(encode("What is the color of the sky?"));
   console.log(pigLatin("What is the color of the sky?", "ay "));
  console.log(palindrome("What is the color of the sky?"));
};

displayMessage();

messageMixer.js

let MessageMixer = {};

 function countCharacter(inputString, inputCharacter) {
  let count = 0;
  let string = inputString.toLowerCase();
  let character = inputCharacter.toLowerCase();
    for (let i = 0; i < string.length; i++) {
      if (string[i] === character) {
         count++;
      }
    }
  return count; 
};

function capitalizeFirstCharacterOfWords(string) {
  let arr = string.split(" ");  
    for (let i = 0; i < arr.length; i++) {  
      let word = arr[i];
        arr[i] = word[0].toUpperCase() + word.substring(1); 
    }
  return arr.join(" "); 
};


 function reverseWord(word) {
  return word.split("").reverse().join("");
};

function reverseAllWords(sentence) {
  let words = sentence.split(' ');
    for (let i = 0; i < words.length; i++) {
      words[i] = reverseWord(words[i]);
    }
   return words.join(" ");
};


function replaceFirstOccurence(string, toBeReplaced, replaceWith) {
  return string.replace(toBeReplaced, replaceWith);
};


function replaceAllOccurrences(string, toBeReplaced, replaceWith) {
  return string.split(toBeReplaced).join(replaceWith);
};

function encode(string) {
  const replacementObject = { 
    a: '@',
    s: '$',
    i: '!',
    o: '0' 
  };
    for (let key in replacementObject) {
      string = replaceAllOccurrences(string, key, replacementObject[key]); 
    }	
    return string;
};

function palindrome(str){
  return `${str}
${reverseWord(str)}`;
};

function pigLatin(sentence, character){
  return sentence.split(' ').join(character +' '); 
};


export {MessageMixer, countCharacter, capitalizeFirstCharacterOfWords, reverseWord, reverseAllWords, replaceFirstOccurence, replaceAllOccurrences, encode, palindrome, pigLatin};