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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Useful Array Methods

Blaize Lange
Blaize Lange
2,298 Points

Why does he write a conditional statement within a conditional statement?

(for those that can't see the video)

He writes a while loop like this

while(){

if(){

}else if(){

}else{

if(){

}else

  }
 }
}

I don't understand why use the second if() after the else{} instead of just adding one more else if{} I wrote the code like this and it works just fine.

while (true) {
  search = prompt("Search for a product in our store. Type 'list' to show all of the produce and 'quit' to exit");
  search = search.toLowerCase();
  if ( search === 'quit') {
    break;
  }else if ( search === 'list'){
    print( inStock.join(', '));
  }else if ( inStock.indexOf(search) > -1){
   print( 'Yes, we have ' + search + ' in the store.');
   }else{
     print( search + ' is not in stock.');
  }
}

I know there is multiple ways of writing the same code but I want to know if there is any reason he chose to write it that way.

1 Answer

Gyorgy Andorka
Gyorgy Andorka
13,811 Points

Yeah, the two branchings are equivalent for the computer, the first one just better grasps the logical structure of the process you want to translate into code. (At the top level, there are the three different options for the user: either to quit, to list all the items, or (else) to search for a specific item. This last option has two possible outcomes - the item is either in stock or not.)