* chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
		
			
				
	
	
		
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			158 lines
		
	
	
		
			2.6 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| ---
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| id: 56533eb9ac21ba0edf2244e0
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| title: Replacing If Else Chains with Switch
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| challengeType: 1
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| videoUrl: 'https://scrimba.com/c/c3JE8fy'
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| forumTopicId: 18266
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| dashedName: replacing-if-else-chains-with-switch
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| ---
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| 
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| # --description--
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| 
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| If you have many options to choose from, a `switch` statement can be easier to write than many chained `if`/`else if` statements. The following:
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| 
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| ```js
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| if (val === 1) {
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|   answer = "a";
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| } else if (val === 2) {
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|   answer = "b";
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| } else {
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|   answer = "c";
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| }
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| ```
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| 
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| can be replaced with:
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| 
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| ```js
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| switch(val) {
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|   case 1:
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|     answer = "a";
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|     break;
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|   case 2:
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|     answer = "b";
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|     break;
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|   default:
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|     answer = "c";
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| }
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| ```
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| 
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| # --instructions--
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| 
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| Change the chained `if`/`else if` statements into a `switch` statement.
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| 
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| # --hints--
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| 
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| You should not use any `else` statements anywhere in the editor
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| 
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| ```js
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| assert(!/else/g.test(code));
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| ```
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| 
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| You should not use any `if` statements anywhere in the editor
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| 
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| ```js
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| assert(!/if/g.test(code));
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| ```
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| 
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| You should have at least four `break` statements
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| 
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| ```js
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| assert(code.match(/break/g).length >= 4);
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| ```
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| 
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| `chainToSwitch("bob")` should be the string `Marley`
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| 
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| ```js
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| assert(chainToSwitch('bob') === 'Marley');
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| ```
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| 
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| `chainToSwitch(42)` should be the string `The Answer`
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| 
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| ```js
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| assert(chainToSwitch(42) === 'The Answer');
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| ```
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| 
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| `chainToSwitch(1)` should be the string `There is no #1`
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| 
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| ```js
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| assert(chainToSwitch(1) === 'There is no #1');
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| ```
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| 
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| `chainToSwitch(99)` should be the string `Missed me by this much!`
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| 
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| ```js
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| assert(chainToSwitch(99) === 'Missed me by this much!');
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| ```
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| 
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| `chainToSwitch(7)` should be the string `Ate Nine`
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| 
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| ```js
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| assert(chainToSwitch(7) === 'Ate Nine');
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| ```
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| 
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| `chainToSwitch("John")` should be `""` (empty string)
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| 
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| ```js
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| assert(chainToSwitch('John') === '');
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| ```
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| 
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| `chainToSwitch(156)` should be `""` (empty string)
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| 
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| ```js
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| assert(chainToSwitch(156) === '');
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| ```
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| 
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| # --seed--
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| 
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| ## --seed-contents--
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| 
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| ```js
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| function chainToSwitch(val) {
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|   var answer = "";
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|   // Only change code below this line
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| 
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|   if (val === "bob") {
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|     answer = "Marley";
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|   } else if (val === 42) {
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|     answer = "The Answer";
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|   } else if (val === 1) {
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|     answer = "There is no #1";
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|   } else if (val === 99) {
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|     answer = "Missed me by this much!";
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|   } else if (val === 7) {
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|     answer = "Ate Nine";
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|   }
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| 
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|   // Only change code above this line
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|   return answer;
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| }
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| 
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| chainToSwitch(7);
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| ```
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| 
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| # --solutions--
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| 
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| ```js
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| function chainToSwitch(val) {
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|   var answer = "";
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| 
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|   switch(val) {
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|     case "bob":
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|       answer = "Marley";
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|       break;
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|     case 42:
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|       answer = "The Answer";
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|       break;
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|     case 1:
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|       answer = "There is no #1";
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|       break;
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|     case 99:
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|       answer = "Missed me by this much!";
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|       break;
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|     case 7:
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|       answer = "Ate Nine";
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|   }
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|   return answer;
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| }
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| ```
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