JavaScript Tips
@javascript_tips
Tips and tricks to make the most of JavaScript and avoid gotchas.
Bunları beğenebilirsin
Arrow functions are not yet supported in Safari, IE and Opera Mini. #javascript #es6 #tip caniuse.com/#feat=arrow-fu…
// ES5 var posNums = nums.filter(function (x) { return x > 0; }); // #ES6 var posNums = nums.filter(x => x > 0); #javascript #tip
#ES6 arrow functions do not have their own 'this'. The value of this inside an arrow function is always inherited from the enclosing scope.
Code is temporary. It exists while it is useful. If code is replaced by better code, good! If code can be deleted, celebrate! #JavaScript
Shorthand for #es6 arrow function with single argument: var f = x => { return x*x; }; // equivalent to var f = (x) => { return x*x; };
Shorthand for #es6 arrow function with single return statement: var f = (x) => x*x; // equivalent to var f = (x) => { return x*x; };
ES6 arrow functions: var normalFunc = function(x) { return x * x; }; var arrowFunc = (x) => { return x*x; }; #javascript #tips
#javascript 'new' keyword: function A() { this.x = 1; this.y = 2; } var a1 = new A(); var a2 = new A(); a1.x++; a1.x; // 2 a2.x; // 1
Usage of the 'arguments' local variable: function foo() { console.log(arguments); } foo(1, 2, 3, 4); // [1, 2, 3, 4] #javascript #tip
Use #es6 in your javascript code today with @babeljs! hacks.mozilla.org/2015/06/es6-in…
hacks.mozilla.org
ES6 In Depth: Using ES6 today with Babel and Broccoli – Mozilla Hacks - the Web developer blog
ES6 In Depth is a series on new features being added to the JavaScript programming language in the 6th Edition of the ECMAScript standard, ES6 for short. ES6 ...
Convert CSV to array: var str = "apple, peach, orange"; var fruitsArray = str.split(","); // ['apple', 'peach', 'orange'] #javascript #tip
#JavaScript array to csv: var fruits = ['apple', 'peaches', 'oranges']; var str = fruits.valueOf(); // apple,peaches,oranges #js #tips
Remove duplicates from array: var deduped = [ 1, 1, 'a', 'a'].filter(function (x, i, arr) { return arr.indexOf(x) === i; }); // [1, 'a']
Flattening an array : var myArray = [[1, 2], [], [3]]; var flatArray = [].concat.apply([], myArray); // flatArray is [1, 2, 3] #javascript
Getting a UNIX timestamp in #JavaScript: var dateTime = Date.now(); var timestamp = Math.floor(dateTime / 1000); #tips #js
To see a function's code, concatenate it with the empty string : console.log(funcVariable + ''); #javascript #tips
The && operator first evaluates the expression on the left. If falsy, false is returned; it does not bother to evaluate the right operand.
JavaScript Falsy Values: null, false, 0 undefined, NaN, and “” (this last item is an empty string). #javascript #tips
Infinity, which is a special number like NaN, is truthy; it is not falsy, while NaN is falsy. #javascript #tips
Calculate max/min in an array: var arr = [1, 2, 3, 4]; Math.max.apply(null, arr) // 4 Math.min.apply(null, arr) // 1 #javascript #tips
United States Trendler
- 1. Cheney 52.3K posts
- 2. #ExpediaChat N/A
- 3. First Take 43.6K posts
- 4. Sedition 101K posts
- 5. Cam Newton 2,778 posts
- 6. Nano Banana Pro 17.2K posts
- 7. Stephen A 38.7K posts
- 8. Treason 63.3K posts
- 9. SEDITIOUS BEHAVIOR 17.8K posts
- 10. Trump and Vance 31.2K posts
- 11. Bush 56.2K posts
- 12. #AcousticPianoSnowGlobe 2,073 posts
- 13. Constitution 89.2K posts
- 14. #LoveDesignFinalEP 387K posts
- 15. FINAL DRAFT FINAL LOVE 424K posts
- 16. Eddie Hennessy N/A
- 17. Go Bills 6,582 posts
- 18. #XboxPartnerPreview 2,643 posts
- 19. Husqvarna 1,293 posts
- 20. Commander in Chief 39.4K posts
Something went wrong.
Something went wrong.