Just TEST 30 seconds of code mini version
Curated collection of useful JavaScript snippets that you can understand in 20 seconds or less.
- Use Ctrl + F or command + F to search for a snippet.
- You can import these snippets into your text editor of choice (VSCode, Atom, Sublime)
Package
You can find a package details npm.
# With npm
npm install jsmp-infra-useful-snippets-js
Usage examples
// ES Modules
import {compact} from 'jsmp-infra-useful-snippets-js';
compact([0, 1, false, 2, '', 3, 'a', 'e' * 23, NaN, 's', 34]);
To import snippets with Node:
const compact = require('jsmp-infra-useful-snippets-js').compact;
compact([0, 1, false, 2, '', 3, 'a', 'e' * 23, NaN, 's', 34]);
const {compact} = require('jsmp-infra-useful-snippets-js');
compact([0, 1, false, 2, '', 3, 'a', 'e' * 23, NaN, 's', 34]);
Table of Contents
📚 Array
View contents
📜 String
View contents
📚 Array
compact
Removes falsey values from an array.
Use Array.filter()
to filter out falsey values (false
, null
, 0
, ""
, undefined
, and NaN
).
const compact = arr => arr.filter(Boolean);
Examples
compact([0, 1, false, 2, '', 3, 'a', 'e' * 23, NaN, 's', 34]); // [ 1, 2, 3, 'a', 's', 34 ]
difference
Returns the difference between two arrays.
Create a Set
from b
, then use Array.filter()
on a
to only keep values not contained in b
.
const difference = (a, b) => {
const s = new Set(b);
return a.filter(x => !s.has(x));
};
Examples
difference([1, 2, 3], [1, 2, 4]); // [3]
union
Returns every element that exists in any of the two arrays once.
Create a Set
with all values of a
and b
and convert to an array.
const union = (a, b) => Array.from(new Set([...a, ...b]));
Examples
union([1, 2, 3], [4, 3, 2]); // [1,2,3,4]
Examples
const users = [{ name: 'fred', age: 48 }, { name: 'barney', age: 36 }, { name: 'fred', age: 40 }];
orderBy(users, ['name', 'age'], ['asc', 'desc']); // [{name: 'barney', age: 36}, {name: 'fred', age: 48}, {name: 'fred', age: 40}]
orderBy(users, ['name', 'age']); // [{name: 'barney', age: 36}, {name: 'fred', age: 40}, {name: 'fred', age: 48}]
📜 String
capitalizeEveryWord
Capitalizes the first letter of every word in a string.
Use String.replace()
to match the first character of each word and String.toUpperCase()
to capitalize it.
const capitalizeEveryWord = str => str.replace(/\b[a-z]/g, char => char.toUpperCase());
Examples
capitalizeEveryWord('hello world!'); // 'Hello World!'
reverseString
Reverses a string.
Use the spread operator (...
) and Array.reverse()
to reverse the order of the characters in the string.
Combine characters to get a string using String.join('')
.
const reverseString = str => [...str].reverse().join('');
Examples
reverseString('foobar'); // 'raboof'
truncateString
Truncates a string up to a specified length.
Determine if the string's length
is greater than num
.
Return the string truncated to the desired length, with '...'
appended to the end or the original string.
const truncateString = (str, num) =>
str.length > num ? str.slice(0, num > 3 ? num - 3 : num) + '...' : str;
Examples
truncateString('boomerang', 7); // 'boom...'
Credits
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