update comments.

Author: davigl

arguments-optional.js

@@ -1,30 +1,31 @@
 /*
 Create a function that sums two arguments together. 
-If only one argument is provided, then return a function that expects one argument and returns the sum.
+If only one argument is provided, then return a function that expects one argument 
+and returns the sum.
 
 For example, addTogether(2, 3) should return 5, and addTogether(2) should return a function.
 */
 
 function addTogether() {
-  const checkType = (number) => {
-    if (typeof(number) === "number") {
+  const checkType = number => {
+    if (typeof number === "number") {
       return true;
     } else return false;
-  }
+  };
 
   if (arguments.length > 1) {
     let x = arguments[0];
     let y = arguments[1];
-    
-    if (checkType(x) && checkType(y)) return (x + y);
+
+    if (checkType(x) && checkType(y)) return x + y;
   } else if (arguments.length === 1) {
     let z = arguments[0];
 
     if (checkType(arguments[0])) {
-      return (arg2) => {
-     	  if (checkType(arg2)) return (z + arg2);
-      }
-    }    
+      return arg2 => {
+        if (checkType(arg2)) return z + arg2;
+      };
+    }
   }
 }
 

convert-html-entities.js

@@ -1,13 +1,14 @@
 /*
-Convert the characters &, <, >, " (double quote), and ' (apostrophe), in a string to their corresponding HTML entities.
+Convert the characters &, <, >, " (double quote), and ' (apostrophe), 
+in a string to their corresponding HTML entities.
 */
 
 function convertHTML(str) {
-  str = str.replace(/&/g, "&amp;")
-  str = str.replace(/</g, "&lt;")
-  str = str.replace(/>/g, "&gt;")
-  str = str.replace(/"/g, "&quot;")
-  str = str.replace(/'/g, "&apos;")
+  str = str.replace(/&/g, "&amp;");
+  str = str.replace(/</g, "&lt;");
+  str = str.replace(/>/g, "&gt;");
+  str = str.replace(/"/g, "&quot;");
+  str = str.replace(/'/g, "&apos;");
 
   return str;
 }

diff-two-arrays.js

@@ -1,19 +1,25 @@
 /*
-Compare two arrays and return a new array with any items only found in one of the two given arrays, but not both. In other words, return the symmetric difference of the two arrays.
+Compare two arrays and return a new array with any items only found in one of the
+two given arrays, but not both. 
+
+In other words, return the symmetric difference of the two arrays.
 */
 
 const filterArray = (arr, arr2) => {
-  let newArray = arr.filter((value) => {
+  let newArray = arr.filter(value => {
     if (arr2.indexOf(value) < 0) return value;
   });
 
   return newArray;
-}
+};
 
 function diffArray(arr1, arr2) {
   var newArr = [...filterArray(arr2, arr1), ...filterArray(arr1, arr2)];
 
   return newArr;
 }
 
-diffArray(["andesite", "grass", "dirt", "pink wool", "dead shrub"], ["diorite", "andesite", "grass", "dirt", "dead shrub"]);
+diffArray(
+  ["andesite", "grass", "dirt", "pink wool", "dead shrub"],
+  ["diorite", "andesite", "grass", "dirt", "dead shrub"]
+);

dna-pairing.js

@@ -1,5 +1,6 @@
 /** 
-The DNA strand is missing the pairing element. Take each character, get its pair, and return the results as a 2d array.
+The DNA strand is missing the pairing element. Take each character, get its pair,
+and return the results as a 2d array.
 
 Base pairs are a pair of AT and CG. Match the missing element to the provided character.
 
@@ -8,20 +9,20 @@ Return the provided character as the first element in each array.
 
 const search = (char, pairs) => {
   switch (char) {
-      case "T":
-        pairs.push(["T", "A"]);
-        break;
-      case "A":
-        pairs.push(["A", "T"]);
-        break;
-      case "C":
-        pairs.push(["C", "G"]);
-        break;
-      case "G":
-        pairs.push(["G", "C"]);
-        break;
+    case "T":
+      pairs.push(["T", "A"]);
+      break;
+    case "A":
+      pairs.push(["A", "T"]);
+      break;
+    case "C":
+      pairs.push(["C", "G"]);
+      break;
+    case "G":
+      pairs.push(["G", "C"]);
+      break;
   }
-}
+};
 
 function pairElement(str) {
   var pairs = [];

drop-it.js

@@ -1,5 +1,7 @@
 /*
-Given the array arr, iterate through and remove each element starting from the first element (the 0 index) until the function func returns true when the iterated element is passed through it.
+Given the array arr, iterate through and remove each element starting from 
+the first element (the 0 index) until the function func returns true when the
+iterated element is passed through it.
 */
 
 function dropElements(arr, func) {
@@ -15,4 +17,8 @@ function dropElements(arr, func) {
   return updatedArray;
 }
 
-console.log(dropElements([1, 2, 3, 4], function(n) {return n >= 3; }));
+console.log(
+  dropElements([1, 2, 3, 4], function(n) {
+    return n >= 3;
+  })
+);

everything-be-true.js

@@ -1,13 +1,24 @@
 /*
-Check if the predicate (second argument) is truthy on all elements of a collection (first argument).
+Check if the predicate (second argument) is truthy on all elements of a collection 
+(first argument).
 */
 
 function truthCheck(collection, pre) {
   for (let i = 0; i < collection.length; i++) {
-    if (!(collection[i][pre])) return false;
+    if (!collection[i][pre]) return false;
   }
 
   return true;
 }
 
-console.log(truthCheck([{"user": "Tinky-Winky", "sex": "male"}, {"user": "Dipsy", "sex": "male"}, {"user": "Laa-Laa", "sex": "female"}, {"user": "Po", "sex": "female"}], "sex"));
+console.log(
+  truthCheck(
+    [
+      { user: "Tinky-Winky", sex: "male" },
+      { user: "Dipsy", sex: "male" },
+      { user: "Laa-Laa", sex: "female" },
+      { user: "Po", sex: "female" }
+    ],
+    "sex"
+  )
+);

map-the-debris.js

@@ -1,5 +1,6 @@
 /*
-Return a new array that transforms the elements' average altitude into their orbital periods (in seconds).
+Return a new array that transforms the elements' average altitude into their 
+orbital periods (in seconds).
 
 The array will contain objects in the format {name: 'name', avgAlt: avgAlt}.
 */
@@ -9,16 +10,15 @@ function orbitalPeriod(arr) {
   var earthRadius = 6367.4447;
 
   for (let i = 0; i < arr.length; i++) {
-    let orbitalPeriodCalc = (2 * Math.PI) * Math.sqrt(
-      Math.pow(earthRadius + arr[i]['avgAlt'], 3) / GM
-    )
+    let orbitalPeriodCalc =
+      2 * Math.PI * Math.sqrt(Math.pow(earthRadius + arr[i]["avgAlt"], 3) / GM);
 
-    delete arr[i]['avgAlt'];
+    delete arr[i]["avgAlt"];
 
-    arr[i]['orbitalPeriod'] = Math.round(orbitalPeriodCalc);
+    arr[i]["orbitalPeriod"] = Math.round(orbitalPeriodCalc);
   }
 
   return arr;
 }
 
-console.log(orbitalPeriod([{name : "sputnik", avgAlt : 35873.5553}]));
+console.log(orbitalPeriod([{ name: "sputnik", avgAlt: 35873.5553 }]));

missing-letters.js

@@ -9,7 +9,7 @@ function fearNotLetter(str) {
     let actualLetterCode = str.charCodeAt(i);
     let nextLetterCode = str.charCodeAt(i + 1);
 
-    if ((actualLetterCode + 1) != nextLetterCode) {
+    if (actualLetterCode + 1 != nextLetterCode) {
       return String.fromCharCode(actualLetterCode + 1);
     }
   }

pig-latin.js

@@ -1,7 +1,8 @@
 /*
 Translate the provided string to pig latin.
 
-Pig Latin takes the first consonant (or consonant cluster) of an English word, moves it to the end of the word and suffixes an "ay".
+Pig Latin takes the first consonant (or consonant cluster) of an English word,
+moves it to the end of the word and suffixes an "ay".
 
 If a word begins with a vowel you just add "way" to the end.
 
@@ -18,7 +19,7 @@ function translatePigLatin(str) {
     str = str.concat("way");
   } else if (globalVowels.test(str)) {
     for (let i = 0; i < str.length - 1; i++) {
-      if (!(startVowel.test(str))) {
+      if (!startVowel.test(str)) {
         str = str.slice(1, str.length).concat(str.charAt(0));
       } else {
         break;

search-and-replace.js

@@ -1,5 +1,6 @@
 /*
-Perform a search and replace on the sentence using the arguments provided and return the new sentence.
+Perform a search and replace on the sentence using the arguments provided and return
+the new sentence.
 
 First argument is the sentence to perform the search and replace on.
 
@@ -8,12 +9,14 @@ Second argument is the word that you will be replacing (before).
 Third argument is what you will be replacing the second argument with (after).
 
 Note
-Preserve the case of the first character in the original word when you are replacing it. For example if you mean to replace the word "Book" with the word "dog", it should be replaced as "Dog"
-*/
 
+Preserve the case of the first character in the original word when you are replacing it.
+For example if you mean to replace the word "Book" with the word "dog", 
+it should be replaced as "Dog"
+*/
 
 function myReplace(str, before, after) {
-  let regex = /^[A-Z]/
+  let regex = /^[A-Z]/;
 
   if (regex.test(before)) {
     after = after.charAt(0).toUpperCase() + after.slice(1);

seek-and-destroy.js

@@ -1,5 +1,7 @@
 /*
-You will be provided with an initial array (the first argument in the destroyer function), followed by one or more arguments. Remove all elements from the initial array that are of the same value as these arguments.
+You will be provided with an initial array (the first argument in the destroyer function),
+followed by one or more arguments. Remove all elements from the initial array that are of
+the same value as these arguments.
 
 Note
 You have to use the arguments object.
@@ -11,7 +13,7 @@ const destroy = (arr, number) => {
   });
 
   return arr;
-}
+};
 
 function destroyer(arr) {
   let keys = Object.keys(arguments);

smallest-common-multiple.js

@@ -1,5 +1,6 @@
 /*
-Find the smallest common multiple of the provided parameters that can be evenly divided by both, as well as by all sequential numbers in the range between these parameters.
+Find the smallest common multiple of the provided parameters that can be evenly divided by both,
+as well as by all sequential numbers in the range between these parameters.
 */
 
 function smallestCommons(arr) {
@@ -21,4 +22,4 @@ function smallestCommons(arr) {
   }
 }
 
-smallestCommons([1,5]);
+smallestCommons([1, 5]);

sorted-union.js

@@ -1,22 +1,25 @@
 /*
-Write a function that takes two or more arrays and returns a new array of unique values in the order of the original provided arrays.
+Write a function that takes two or more arrays and returns a new array of unique values
+in the order of the original provided arrays.
 
-In other words, all values present from all arrays should be included in their original order, but with no duplicates in the final array.
+In other words, all values present from all arrays should be included in their original 
+order, but with no duplicates in the final array.
 
-The unique numbers should be sorted by their original order, but the final array should not be sorted in numerical order.
+The unique numbers should be sorted by their original order, but the final array should not 
+be sorted in numerical order.
 */
 
-function onlyUnique(value, index, self) { 
-    return self.indexOf(value) === index;
+function onlyUnique(value, index, self) {
+  return self.indexOf(value) === index;
 }
 
 function uniteUnique(arr) {
-  let unique = []
+  let unique = [];
 
   for (let key in arguments) {
     unique.push(...arguments[key]);
   }
-  
+
   unique = unique.filter(onlyUnique);
 
   return unique;

sum-all-numbers-in-a-range.js

@@ -1,5 +1,6 @@
 /*
-We'll pass you an array of two numbers. Return the sum of those two numbers plus the sum of all the numbers between them. The lowest number will not always come first.
+We'll pass you an array of two numbers. Return the sum of those two numbers plus
+the sum of all the numbers between them. The lowest number will not always come first.
 */
 
 function sumAll(arr) {

sum-all-odd-fibonacci-numbers.js

@@ -1,8 +1,8 @@
 /*
-Given a positive integer num, return the sum of all odd Fibonacci numbers that are less than or equal to num.
+Given a positive integer num, return the sum of all odd Fibonacci numbers that are 
+less than or equal to num.
 */
 
-
 function sumFibs(num) {
   var previousNumber = 0;
   var currentNumber = 1;

sum-all-primes.js

@@ -1,14 +1,17 @@
 /*
-A prime number is a whole number greater than 1 with exactly two divisors: 1 and itself. For example, 2 is a prime number because it is only divisible by 1 and 2. In contrast, 4 is not prime since it is divisible by 1, 2 and 4.
+A prime number is a whole number greater than 1 with exactly two divisors: 1 and
+itself. For example, 2 is a prime number because it is only divisible by 1 and 2.
+
+In contrast, 4 is not prime since it is divisible by 1, 2 and 4.
 */
 
 const isPrime = number => {
   for (let i = 2, s = Math.sqrt(number); i <= s; i++) {
     if (number % i === 0) return false;
   }
-  
+
   return number > 1;
-}
+};
 
 function sumPrimes(num) {
   let result = 0;

wherefore-art-thou.js

@@ -1,5 +1,9 @@
 /*
-Make a function that looks through an array of objects (first argument) and returns an array of all objects that have matching name and value pairs (second argument). Each name and value pair of the source object has to be present in the object from the collection if it is to be included in the returned array.
+Make a function that looks through an array of objects (first argument) and returns
+an array of all objects that have matching name and value pairs (second argument). 
+
+Each name and value pair of the source object has to be present in the object from 
+the collection if it is to be included in the returned array.
 */
 
 function whatIsInAName(collection, source) {
@@ -21,4 +25,13 @@ function whatIsInAName(collection, source) {
   return arr;
 }
 
-console.log(whatIsInAName([{ first: "Romeo", last: "Montague" }, { first: "Mercutio", last: null }, { first: "Tybalt", last: "Capulet" }], { last: "Capulet" }));
+console.log(
+  whatIsInAName(
+    [
+      { first: "Romeo", last: "Montague" },
+      { first: "Mercutio", last: null },
+      { first: "Tybalt", last: "Capulet" }
+    ],
+    { last: "Capulet" }
+  )
+);