@locustjs/extensions-string v2.0.2
About
This library contains extensions for string.
Install
npm i @locustjs/extensions-stringImport
CommonJs
var someFn = require('@locustjs/extensions-string').someFn;ES6
import { someFn } from '@locustjs/extensions-string'Usage
string extension methods can be used in three ways.
1. Direct call
import { replaceAll } from '@locustjs/extensions-string';
const str = 'Hello';
console.log(replaceAll(str, 'l', '$')); // He$$oPros
- Works on
undefinedvariables as well.
Cons
- Requires
import
2. As extension method on string instances
const str = 'Hello';
console.log(str.replaceAll('l', '$')); // He$$oPros
- Does not require
import - More readable code
Cons
- Does not work on
undefinedvariables
3. As static method on String
const str = 'Hello';
console.log(String.replaceAll(str, 'l', '$')); // He$$oPros
- Works on
undefinedvariables as well. - Does not require
import
Cons
- More characters to type
- Less readable
Classes
StringBuilder
A helper class to concatenate strings more efficiently. It uses an internal array, places given strings inside the array, extends array size if needed, joins the array upon calling toString method and resets the array.
const sb = new StringBuilder();
sb.append('Hello')
sb.append(' World')
sb.append('\n')
sb.append('Goodbye')
console.log(sb.toString());
/* output:
Hello World
Goodbye
*/Functions
replaceAll(str, find, replace)
Replaces find with replace in str string.
let str = 'to be or not to be';
// usage 1: direct call
console.log(replaceAll(str, 'to', '2'));
// usage 2: as an extension method
console.log(str.replaceAll('to', '2'));
// usage 3: as static method
console.log(String.replaceAll(str, 'to', '2'));
/* output:
2 be or not 2 be
*/reverse(str)
Reverses str string.
let str = 'Hello World';
// usage 1: direct call
console.log(reverse(str));
// usage 2: as an extension method
console.log(str.reverse());
// usage 3: as static method
console.log(String.reverse(str));
/* output:
dlroW olleH
*/ltrim(str)
Removes white-space character from left-side of str string.
let str = ' Hello ';
// usage 1: direct call
console.log(`"${ltrim(str)}"`);
// usage 2: as an extension method
console.log(`"${str.ltrim()}"`);
// usage 3: as static method
console.log(`"${String.ltrim(str)}"`);
/* output:
"Hello "
*/rtrim(str)
Removes white-space character from right-side of str string.
let str = ' Hello ';
// usage 1: direct call
console.log(`"${rtrim(str)}"`);
// usage 2: as an extension method
console.log(`"${str.rtrim()}"`);
// usage 3: as static method
console.log(`"${String.rtrim(str)}"`);
/* output:
" Hello"
*/toArray(str)
Converts str string into an array of ascii-codes.
let str = 'Hello';
// usage 1: direct call
console.log(toArray(str));
// usage 2: as an extension method
console.log(str.toArray());
// usage 3: as static method
console.log(String.toArray(str));
/* output:
[72, 101, 108, 108, 111]
*/
str = 'سلام';
// usage 1: direct call
console.log(toArray(str));
// usage 2: as an extension method
console.log(str.toArray());
// usage 3: as static method
console.log(String.toArray(str));
/* output:
[1587, 1604, 1575, 1605]
*/fromArray(arr)
Converts arr array into a string.
let arr = [72, 101, 108, 108, 111];
// usage 1: direct call
console.log(fromArray(arr));
// usage 3: as static method
console.log(String.fromArray(arr));
/* output:
Hello
*/toBytes(str)
Converts str string into an array of unsigned bytes.
let str = 'سلام';
// usage 1: direct call
console.log(toBytes(str));
// usage 2: as an extension method
console.log(str.toBytes());
// usage 3: as static method
console.log(String.toBytes(str));
/* output:
[216, 179, 217, 132, 216, 167, 217, 133]
*/fromBytes(arr)
Converts arr byte-array into a string.
let arr = new Uint8Array([216, 179, 217, 132, 216, 167, 217, 133])
// usage 1: direct call
console.log(fromBytes(arr));
// usage 3: as static method
console.log(String.fromBytes(arr));
/* output:
سلام
*/Character type checking
// checks if input is only one character
console.log(String.isCharacter('a')); // true
console.log(String.isCharacter('ab')); // false
// punctuation letters: '.', ',', ';', ':', '?', '!', '(', ')', '-', "'", '"', '/', '\\', '{', '}', '[', ']', '%', '#'
console.log(String.isPunctuation('.')); // true
console.log(String.isPunctuation('+')); // false
// control characters: '~', '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '_', '+', '|', '<', '>', '?', ':', '{', '}', '[', ']', ';', '"', "'", ',', '.', '/', '-', '=', '\\', '`'
console.log(String.isControl('!')); // true
console.log(String.isControl('a')); // false
// checks if input is an alphabet character, upper or lower.
console.log(String.isAlpha('a')); // true
console.log(String.isAlpha('2')); // false
// isLetter() is the same as isAlpha()
console.log(String.isLetter('a')); // true
console.log(String.isLetter('2')); // false
// checks if input is a lower alphabet character
console.log(String.isLower('a')); // true
console.log(String.isLower('A')); // false
// checks if input is an upper alphabet character
console.log(String.isUpper('A')); // true
console.log(String.isUpper('a')); // false
// checks if input is a digit number 0-9
console.log(String.isDigit('2')); // true
console.log(String.isDigit('a')); // false
// checks if input is an alphabet or digit character
console.log(String.isAlphaNum('a')); // true
console.log(String.isAlphaNum('2')); // true
console.log(String.isAlphaNum('/')); // false
// checks if input is a word string that contains only alphabet, digit or underscore
console.log(String.isWord('abc')); // true
console.log(String.isWord('123')); // true
console.log(String.isWord('a2')); // true
console.log(String.isWord('a b')); // false
console.log(String.isWord('a1 ')); // false
// checks if input is an arithmatic operator: '/', '\\', '+', '-', '(', ')', '%', '^', '*', '++', '--'
console.log(String.isArithmatic('+')); // true
console.log(String.isArithmatic('&')); // false
// checks if input is a logical operator: '&&', '||', '!'
console.log(String.isLogic('&&')); // true
console.log(String.isLogic('&')); // false
// checks if input is a bitwise operator: '&', '|', '>>', '<<'
console.log(String.isBitwise('&')); // true
console.log(String.isBitwise('+')); // false
// checks if input is a comparison operator: '==', '!=', '<>', '>', '<', '>=', '<=', '===', '!=='
console.log(String.isComparison('>')); // true
console.log(String.isComparison('!')); // false
// checks if input is a whitespace character or string
console.log(String.isWhitespace(' ')); // true
console.log(String.isWhitespace(' ')); // true
console.log(String.isWhitespace('\n')); // true
console.log(String.isWhitespace(' \n')); // true
console.log(String.isWhitespace('\t')); // true
console.log(String.isWhitespace('=')); // false
// checks if input is an arithmatic, logical, bitwise or comparison character sequence
console.log(String.isMath('+')); // true
console.log(String.isMath('&')); // true
console.log(String.isMath('&&')); // true
console.log(String.isMath('>')); // true
console.log(String.isMath('<=')); // true
console.log(String.isMath('!')); // true
console.log(String.isMath('/')); // true
console.log(String.isMath('||')); // true
console.log(String.isMath('|')); // falsestringify(str, char = '"')
Adds string characters to both sides of str string.
let str = 'Hello';
// usage 1: direct call
console.log(stringify(str)); // "Hello"
console.log(stringify(str, "'")); // 'Hello'
// usage 2: as an extension method
console.log(str.stringify()); // "Hello"
console.log(str.stringify("'")); // 'Hello'
// usage 3: as static method
console.log(String.stringify(str)); // "Hello"
console.log(String.stringify(str, "'")); // 'Hello'unString(str)
Removes string characters from either side(s) of str string.
let str = '"Hello"';
// usage 1: direct call
console.log(unString(str));
// usage 2: as an extension method
console.log(str.unString());
// usage 3: as static method
console.log(String.unString(str));
/* output:
Hello
*/toggleCase(str) or changeCase(str)
Changes alphabetic cases of alphabet characters in str string.
let str = 'Google Play';
// usage 1: direct call
console.log(changeCase(str));
// usage 2: as an extension method
console.log(str.changeCase());
// usage 3: as static method
console.log(String.changeCase(str));
/* output:
gOOGLE pLAY
*/pascalCase(str)
Turns first letters of words into uppercase in str string and removes other none-alphabetic characters.
let str = 'john doe';
// usage 1: direct call
console.log(pascalCase(str));
// usage 2: as an extension method
console.log(str.pascalCase());
// usage 3: as static method
console.log(String.pascalCase(str));
/* output:
JohnDoe
*/camelCase(str)
Turns first letters of words into uppercase in str string except first word and removes other none-alphabetic characters.
let str = 'john doe';
// usage 1: direct call
console.log(camelCase(str));
// usage 2: as an extension method
console.log(str.camelCase());
// usage 3: as static method
console.log(String.camelCase(str));
/* output:
johnDoe
*/capitalize(str)
Turns first letters of words into uppercase in str string.
let str = 'to be or not to be';
// usage 1: direct call
console.log(capitalize(str));
// usage 2: as an extension method
console.log(str.capitalize());
// usage 3: as static method
console.log(String.capitalize(str));
/* output:
To Be Or Not To Be
*/left(str, n)
Returns n characters from left-side of str string.
let str = 'abcdefgh';
// usage 1: direct call
console.log(left(str, 3));
// usage 2: as an extension method
console.log(str.left(3));
// usage 3: as static method
console.log(String.left(str, 3));
/* output:
abc
*/right(str, n)
Returns n characters from right-side of str string.
let str = 'abcdefgh';
// usage 1: direct call
console.log(right(str, 3));
// usage 2: as an extension method
console.log(str.right(3));
// usage 3: as static method
console.log(String.right(str, 3));
/* output:
fgh
*/format(str, ...args)
Formats given str string pattern based on given args arguments.
Example 1:
const pattern = 'My name is {0}; I am {1} years old.';
// usage 1: direct call
console.log(format(pattern, 'John', 23));
// usage 2: as an extension method
console.log(pattern.format('John', 23));
// usage 3: as static method
console.log(String.format(pattern, 'John', 23));
/* output:
My name is John; I am 23 years old.
*/Example 2:
const pattern = 'My name is {name}; I am {age} years old.';
const arg = { name: 'John', age: 23 }
// usage 1: direct call
console.log(format(pattern, arg));
// usage 2: as an extension method
console.log(pattern.format(arg));
// usage 3: as static method
console.log(String.format(pattern, arg));
/* output:
My name is John; I am 23 years old.
*/nsplit(str, separators, callback?)
splits str based on given array of separators, calls callback function on each segment (if callback is specified).
Callback signature:
callback({
input: str,
value: current part,
index: part index,
level: number,
separator: current separator
})If callback returns antyhing, nsplit uses that instead of passed segment.
const str = 'a=10&b=john';
// usage 1: direct call
console.log(nsplit(str, ['&', '=']));
// usage 2: as an extension method
console.log(str.nsplit('John', 23));
// usage 3: as static method
console.log(String.nsplit(str, 'John', 23));
/* output:
[
['a', '10'],
['b', 'john']
]
*/xsplit(str, separator, transforms)
nsplit str string based on given separator, iterates over the segments and and transforms them based on requested transformations..
Possible values for transforms:
trimortltrimorltrtrimorrtupperoruoruplowerorlorlowcamelorcorcampascalorporpaschangecaseorcccapitalizeorcstringifyorsreverseorrorrevunstringorun
const str = 'London, tehran , toKYO, istanbuL';
const transforms = 'trim,lower,capitalize'; // or 't,l,cap'
// i.e. trims, lowercases and captalizes each item
// usage 1: direct call
console.log(xsplit(str, ',', transforms));
// usage 2: as an extension method
console.log(str.xsplit(',', transforms));
// usage 3: as static method
console.log(String.xsplit(str, ',', transforms));
/* output:
[
"London",
"Tehran",
"Tokyo",
"Istanbul"
]
*/