nepsilon/5-handy-javascript-one-liners.md

## 5-handy-javascript-one-liners.md

      
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              5-handy-javascript-one-liners.md
            
          
    5 handy JavaScript one-liners

1. Generate a random string:

Math.random().toString(36).substr(2); 
This simply generates a random float, casts it into a String using base 36 and remove the 2 first chars 0 and.
Note that this is not a replacement for UUID generation.
2. Clone an array:

var newA = myArray.slice(0); 
This will return a copy of the array, ensuring no other variables point to it.
3. Remove HTML tags:

"<b>A</b>".replace(/<[^>]+>/gi, ""); 
This is using a simple regular expression to remove any string that looks like <xxx> where x can be any char, including /.
4. Set a default value:

function foo(opts) {
  var options = opts || {};
} 
You will see this in any decent JS code.
If opts is defined and not “binarily” false it will be assigned to options, otherwise it will assign an empty dictionary {}.
5. Reverse a string:

var str = "Pouet this string.";
str.split('').reverse().join('');
// Output: ".gnirts siht teuoP"
// Keep words order with:
str.split(' ').reverse().join(' ');
// Output: "string. this Pouet" 
// The first example splits on every character, reverses them and puts them back together.
The second splits only on words and joins them back separated by a space.