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Rio Cantre
Rio Cantre

Posted on • Originally published at dev.to

Day 100/100 Reverse Function

#100daysofcode #programming #javascript #motivation

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Declaring Functions

Functions allow you to package up lines of code that you can use (and often reuse) in your programs.

function reversString(reverseMe) { var reversed = ""; for (var i = reverseMe.length - 1; i >= 0; i--) { reversed += reverseMe[i]; } return reversed; }
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The reverseString() function had one parameter: the string to be reversed. In both cases, the parameter is listed as a variable after the function name, inside the parentheses. And, if there were multiple parameters, you would just separate them with commas.

Return statements 

function sayHello() { var message = "Hello!" console.log(message); }
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In the sayHello() function above, a value is printed to the console with console.log, but not explicitly returned with a return statement.

You can write a return statement by using the return keyword followed by the expression or value that you want to return.

function sayHello() { var message = "Hello!" return message; // returns value instead of printing it }
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Function Recap

  • Functions package up code so you can easily use (and reuse) a block of code.

  • Parameters are variables that are used to store the data that's passed into a function for the function to use.

  • Arguments are the actual data that's passed into a function when it is invoked:

function add(x, y) { var sum = x + y; return sum; // return statement }
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Code Snippets 

for(var i=0; i<numbers.length; i++){ for(var j=0; j<numbers[i].length; j++){ if(numbers[i][j]%2===0) numbers[i][j]="even"; else numbers[i][j]="odd"; } } console.log(numbers); var facebookProfile = { name: "Bear", friends: 123, messages: ["Bear loves fish", "Bear loves nap", "Bear love honey"], postMessage: function(message) { facebookProfile.messages.push(message); }, deleteMessage: function(index) { facebookProfile.messages.splice(index, 1); }, addFriend: function() { facebookProfile.friends = facebookProfile.friends + 1; }, removeFriend: function() { if(facebookProfile.friends >0) facebookProfile.friends = facebookProfile.friends - 1; } }; console.log(facebookProfile);
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Summary

Happy Hacking!!!

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