JavaScript: Difference between revisions

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=Internal=
* [[TypeScript]]
=Subjects=
=Subjects=
* [[JavaScript Concepts|Concepts]]
* [[JavaScript Concepts|Concepts]]
* [[JavaScript Operations|Operations]]


=Examples=
=Examples=
Line 13: Line 15:
=Things I've Found Useful While Working with Chrome Console=
=Things I've Found Useful While Working with Chrome Console=


var a = 10;
<syntaxhighlight lang='javascript'>
console.log(a);
var a = 10;
console.log(a);
 
var workersUp = function(targetCnt) {
    return Cluster.workers().length == targetCnt;
};
</syntaxhighlight>
 
A JavaScript identifier must start with lower or upper case letter, underscore (_) or dollar ($). Subsequent characters may include digits.
 
The Underscore identifier: it is frequently used to preface the name of an object's property or method that is private.
 
https://underscorejs.org:
 
<tt>_.range(1, 100000)</tt>: a function to create flexibly numbered lists of integers: https://underscorejs.org/#range
 
<tt>_.map(list, iteratee, [context])</tt>: https://underscorejs.org/#map
 
Arrow function expression () =>. The arrow function expression is a syntactically compact alternative to a regular function expression https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions. The basic syntax:
(param1, param2, …, paramN) => { statements }
 
(param1, param2, …, paramN) => expression
// equivalent with:
  => { return expression; }
 
When there is one parameter parentheses are optional:
 
(param) => { statements }
// equivalent with:
param => { statements }

Latest revision as of 19:39, 15 December 2021

Internal

Subjects

Examples

Organizatorium

Things I've Found Useful While Working with Chrome Console

var a = 10;
console.log(a);

var workersUp = function(targetCnt) {
    return Cluster.workers().length == targetCnt;
};

A JavaScript identifier must start with lower or upper case letter, underscore (_) or dollar ($). Subsequent characters may include digits.

The Underscore identifier: it is frequently used to preface the name of an object's property or method that is private.

https://underscorejs.org:

_.range(1, 100000): a function to create flexibly numbered lists of integers: https://underscorejs.org/#range

_.map(list, iteratee, [context]): https://underscorejs.org/#map

Arrow function expression () =>. The arrow function expression is a syntactically compact alternative to a regular function expression https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions. The basic syntax:

(param1, param2, …, paramN) => { statements } 
(param1, param2, …, paramN) => expression
// equivalent with:
 => { return expression; }

When there is one parameter parentheses are optional:

(param) => { statements }
// equivalent with:
param => { statements }