Array
+Uncategorized +
detectDeviceType +negate + +Adapter
+call
Given a key and a set of arguments, call them when given a context. Primarily useful in composition.
+Use a closure to call a stored key with stored arguments.
+const call = ( key, ...args ) => context => context[ key ]( ...args );
+/*
+Promise.resolve( [ 1, 2, 3 ] ).then( call('map', x => 2 * x ) ).then( console.log ) //[ 2, 4, 6 ]
+const map = call.bind(null, 'map')
+Promise.resolve( [ 1, 2, 3 ] ).then( map( x => 2 * x ) ).then( console.log ) //[ 2, 4, 6 ]
+*/
+collectInto
Changes a function that accepts an array into a variadic function.
+Given a function, return a closure that collects all inputs into an array-accepting function.
+const collectInto = fn => ( ...args ) => fn( args );
+/*
+const Pall = collectInto( Promise.all.bind(Promise) )
+let p1 = Promise.resolve(1)
+let p2 = Promise.resolve(2)
+let p3 = new Promise((resolve) => setTimeout(resolve,2000,3))
+Pall(p1, p2, p3).then(console.log)
+*/
+flip
Flip takes a function as an argument, then makes the first argument the last
+Return a closure that takes variadic inputs, and splices the last argument to make it the first argument before applying the rest.
+const flip = fn => (...args) => fn(args.pop(), ...args)
+/*
+let a = {name: 'John Smith'}
+let b = {}
+const mergeFrom = flip(Object.assign)
+let mergePerson = mergeFrom.bind(a)
+mergePerson(b) // == b
+b = {}
+Object.assign(b, a) // == b
+*/
+promisify
Converts an asynchronous function to return a promise.
+Use currying to return a function returning a Promise that calls the original function.
+Use the ...rest operator to pass in all the parameters.
In Node 8+, you can use util.promisify
const promisify = func =>
+ (...args) =>
+ new Promise((resolve, reject) =>
+ func(...args, (err, result) =>
+ err ? reject(err) : resolve(result))
+ );
+// const delay = promisify((d, cb) => setTimeout(cb, d))
+// delay(2000).then(() => console.log('Hi!')) -> Promise resolves after 2s
+spreadOver
Takes a variadic function and returns a closure that accepts an array of arguments to map to the inputs of the function.
+Use closures and the spread operator (...) to map the array of arguments to the inputs of the function.
const spreadOver = fn => argsArr => fn(...argsArr);
+/*
+const arrayMax = spreadOver(Math.max)
+arrayMax([1,2,3]) // -> 3
+arrayMax([1,2,4]) // -> 4
+*/
+Array
arrayGcd
Calculates the greatest common denominator (gcd) of an array of numbers.
Use Array.reduce() and the gcd formula (uses recursion) to calculate the greatest common denominator of an array of numbers.
arrayLcm
Calculates the lowest common multiple (lcm) of an array of numbers.
-Use Array.reduce() and the lcm formula (uses recursion) to calculate the lowest common multiple of an array of numbers.
Calculates the lowest common multiple (lcm) of an array of numbers.
+Use Array.reduce() and the lcm formula (uses recursion) to calculate the lowest common multiple of an array of numbers.
const arrayLcm = arr =>{
const gcd = (x, y) => !y ? x : gcd(y, x % y);
- const lcm = (x, y) => (x*y)/gcd(x, y)
+ const lcm = (x, y) => (x*y)/gcd(x, y);
return arr.reduce((a,b) => lcm(a,b));
}
// arrayLcm([1,2,3,4,5]) -> 60
@@ -300,8 +409,8 @@ Returns the remaining elements.
flatten
Flattens an array.
-Use Array.reduce() to get all elements inside the array and concat() to flatten them.
const flatten = arr => arr.reduce((a, v) => a.concat(v), []);
+Use a new array and concatenate it with the spread input array causing a shallow denesting of any contained arrays.
+const flatten = arr => [ ].concat( ...arr );
// flatten([1,[2],3,4]) -> [1,2,3,4]
flattenDepth
depth to flatten only to a depth of
// flattenDepth([1,[2],[[[3],4],5]], 2) -> [1,2,[3],4,5]
groupBy
Groups the element of an array based on the given function.
+Groups the elements of an array based on the given function.
Use Array.map() to map the values of an array to a function or property name.
Use Array.reduce() to create an object, where the keys are produced from the mapped results.
const groupBy = (arr, func) =>
@@ -333,13 +442,13 @@ Use Array.reduce() to create an object, where the keys are produced
initial
Returns all the elements of an array except the last one.
-Use arr.slice(0,-1)to return all but the last element of the array.
Use arr.slice(0,-1) to return all but the last element of the array.
const initial = arr => arr.slice(0, -1);
// initial([1,2,3]) -> [1,2]
initialize2DArray
Initializes an 2D array of given width and height and value.
-Use Array.map() to generate h rows where each is a new array of size w initialize with value. If value is not provided, default to null.
Initializes a 2D array of given width and height and value.
+Use Array.map() to generate h rows where each is a new array of size w initialize with value. If the value is not provided, default to null.
const initialize2DArray = (w, h, val = null) => Array(h).fill().map(() => Array(w).fill(val));
// initializeArrayWithRange(2, 2, 0) -> [[0,0], [0,0]]
value to use a default value of 0.
last
Returns the last element in an array.
-Use arr.length - 1 to compute index of the last element of the given array and returning it.
Use arr.length - 1 to compute the index of the last element of the given array and returning it.
const last = arr => arr[arr.length - 1];
// last([1,2,3]) -> 3
mapObject
Maps the values of an array to an object using a function, where the key-value pairs consist of the original value as the key and the mapped value.
-Use an anonymous inner function scope to declare an undefined memory space, using closures to store a return value. Use a new Array to stor the array with a map of the function over its data set and a comma operator to return a second step, without needing to move from one context to another (due to closures and order of operations).
Use an anonymous inner function scope to declare an undefined memory space, using closures to store a return value. Use a new Array to store the array with a map of the function over its data set and a comma operator to return a second step, without needing to move from one context to another (due to closures and order of operations).
const mapObject = (arr, fn) =>
(a => (a = [arr, arr.map(fn)], a[0].reduce( (acc,val,ind) => (acc[val] = a[1][ind], acc), {}) )) ( );
/*
@@ -392,7 +501,7 @@ Omit the second argument, n, to get the first element of the array.
pick
Picks the key-value pairs corresponding to the given keys from an object.
-Use Array.reduce() to convert the filtered/picked keys back to a object with the corresponding key-value pair if the key exist in the obj.
Use Array.reduce() to convert the filtered/picked keys back to an object with the corresponding key-value pair if the key exists in the obj.
const pick = (obj, arr) =>
arr.reduce((acc, curr) => (curr in obj && (acc[curr] = obj[curr]), acc), {});
// pick({ 'a': 1, 'b': '2', 'c': 3 }, ['a', 'c']) -> { 'a': 1, 'c': 3 }
@@ -400,7 +509,7 @@ Omit the second argument, n, to get the first element of the array.
pull
Mutates the original array to filter out the values specified.
Use Array.filter() and Array.includes() to pull out the values that are not needed.
-Use Array.length = 0 to mutate the passed in array by resetting it's length to zero and Array.push() to re-populate it with only the pulled values.
Array.length = 0 to mutate the passed in an array by resetting it's length to zero and Array.push() to re-populate it with only the pulled values.
(For a snippet that does not mutate the original array see without)
const pull = (arr, ...args) => {
let argState = Array.isArray(args[0]) ? args[0] : args;
@@ -420,7 +529,7 @@ Use Array.length = 0 to mutate the passed in array by resetting it'
pullAtIndex
Mutates the original array to filter out the values at the specified indexes.
Use Array.filter() and Array.includes() to pull out the values that are not needed.
-Use Array.length = 0 to mutate the passed in array by resetting it's length to zero and Array.push() to re-populate it with only the pulled values.
+Use Array.length = 0 to mutate the passed in an array by resetting it's length to zero and Array.push() to re-populate it with only the pulled values.
Use Array.push() to keep track of pulled values
const pullAtIndex = (arr, pullArr) => {
let removed = [];
@@ -440,7 +549,7 @@ Use Array.push() to keep track of pulled values
pullAtValue
Mutates the original array to filter out the values specified. Returns the removed elements.
Use Array.filter() and Array.includes() to pull out the values that are not needed.
-Use Array.length = 0 to mutate the passed in array by resetting it's length to zero and Array.push() to re-populate it with only the pulled values.
+Use Array.length = 0 to mutate the passed in an array by resetting it's length to zero and Array.push() to re-populate it with only the pulled values.
Use Array.push() to keep track of pulled values
const pullAtValue = (arr, pullArr) => {
let removed = [],
@@ -470,7 +579,7 @@ The func is invoked with three arguments (value, index, array
sample
Returns a random element from an array.
-Use Math.random() to generate a random number, multiply it with length and round it of to the nearest whole number using Math.floor().
+
Use Math.random() to generate a random number, multiply it by length and round it of to the nearest whole number using Math.floor().
This method also works with strings.
const sample = arr => arr[Math.floor(Math.random() * arr.length)];
// sample([3, 7, 9, 11]) -> 9
@@ -498,7 +607,7 @@ This method also works with strings.
tail
Returns all elements in an array except for the first one.
-Return arr.slice(1) if the array's length is more than 1, otherwise return the whole array.
Return arr.slice(1) if the array's length is more than 1, otherwise, return the whole array.
const tail = arr => arr.length > 1 ? arr.slice(1) : arr;
// tail([1,2,3]) -> [2,3]
// tail([1]) -> [1]
@@ -579,6 +688,7 @@ Omit the second argument to determine if the element is entirely visible, or spe
it is partially visible.
const elementIsVisibleInViewport = (el, partiallyVisible = false) => {
const { top, left, bottom, right } = el.getBoundingClientRect();
+ const { innerHeight, innerWidth } = window;
return partiallyVisible
? ((top > 0 && top < innerHeight) || (bottom > 0 && bottom < innerHeight)) &&
((left > 0 && left < innerWidth) || (right > 0 && right < innerWidth))
@@ -625,7 +735,7 @@ Pass a second argument to simulate a link click (true - default) or
scrollToTop
Smooth-scrolls to the top of the page.
Get distance from top using document.documentElement.scrollTop or document.body.scrollTop.
-Scroll by a fraction of the distance from top. Use window.requestAnimationFrame() to animate the scrolling.
window.requestAnimationFrame() to animate the scrolling.
const scrollToTop = () => {
const c = document.documentElement.scrollTop || document.body.scrollTop;
if (c > 0) {
@@ -638,7 +748,7 @@ Scroll by a fraction of the distance from top. Use window.requestAnimation
Date
getDaysDiffBetweenDates
Returns the difference (in days) between two dates.
-Calculate the difference (in days) between to Date objects.
Calculate the difference (in days) between two Date objects.
const getDaysDiffBetweenDates = (dateInitial, dateFinal) => (dateFinal - dateInitial) / (1000 * 3600 * 24);
// getDaysDiffBetweenDates(new Date("2017-12-13"), new Date("2017-12-22")) -> 9
window.requestAnimation
toEnglishDate
Converts a date from American format to English format.
-Use Date.toISOString(), split('T') and replace() to convert a date from American format to English format.
+
Use Date.toISOString(), split('T') and replace() to convert a date from American format to the English format.
Throws an error if the passed time cannot be converted to a date.
const toEnglishDate = (time) =>
{try{return new Date(time).toISOString().split('T')[0].replace(/-/g, '/')}catch(e){return}};
@@ -688,7 +798,7 @@ multiplyAndAdd5(5, 2) -> 15
Curries a function.
Use recursion.
If the number of provided arguments (args) is sufficient, call the passed function f.
-Otherwise return a curried function f that expects the rest of the arguments.
+Otherwise, return a curried function f that expects the rest of the arguments.
If you want to curry a function that accepts a variable number of arguments (a variadic function, e.g. Math.min()), you can optionally pass the number of arguments to the second parameter arity.
const curry = (fn, arity = fn.length, ...args) =>
arity <= args.length
@@ -715,20 +825,6 @@ const multiplyAndAdd5 = pipeFunctions(multiply, add5)
multiplyAndAdd5(5, 2) -> 15
*/
-promisify
Converts an asynchronous function to return a promise.
-Use currying to return a function returning a Promise that calls the original function.
-Use the ...rest operator to pass in all the parameters.
In Node 8+, you can use util.promisify
const promisify = func =>
- (...args) =>
- new Promise((resolve, reject) =>
- func(...args, (err, result) =>
- err ? reject(err) : resolve(result))
- );
-// const delay = promisify((d, cb) => setTimeout(cb, d))
-// delay(2000).then(() => console.log('Hi!')) -> Promise resolves after 2s
-runPromisesInSeries
Runs an array of promises in series.
Use Array.reduce() to create a promise chain, where each promise returns the next promise when resolved.
Clamps num within the inclusive lower and upper bounds.
If lower is greater than upper, swap them.
If num falls within the range, return num.
-Otherwise return the nearest number in the range.
const clampNumber = (num, lower, upper) => {
if(lower > upper) upper = [lower, lower = upper][0];
return (num>=lower && num<=upper) ? num : ((num < lower) ? lower : upper)
@@ -776,7 +872,7 @@ Otherwise return the nearest number in the range.
collatz
Applies the Collatz algorithm.
-If n is even, return n/2. Otherwise return 3n+1.
If n is even, return n/2. Otherwise, return 3n+1.
const collatz = n => (n % 2 == 0) ? (n / 2) : (3 * n + 1);
// collatz(8) --> 4
// collatz(5) --> 16
@@ -813,6 +909,24 @@ Use Array.reduce() to add values into the array, using the sum of t
Array.from({ length: n}).reduce((acc, val, i) => acc.concat(i > 1 ? acc[i - 1] + acc[i - 2] : i), []);
// fibonacci(5) -> [0,1,1,2,3]
fibonacciCountUntilNum
Returns the number of fibonnacci numbers up to num(0 and num inclusive).
Use a mathematical formula to calculate the number of fibonacci numbers until num.
const fibonacciCountUntilNum = num =>
+ Math.ceil(Math.log(num * Math.sqrt(5) + 1/2) / Math.log((Math.sqrt(5)+1)/2));
+// fibonacciCountUntilNum(10) -> 7
+fibonacciUntilNum
Generates an array, containing the Fibonacci sequence, up until the nth term.
+Create an empty array of the specific length, initializing the first two values (0 and 1).
+Use Array.reduce() to add values into the array, using the sum of the last two values, except for the first two.
+Uses a mathematical formula to calculate the length of the array required.
const fibonacciUntilNum = num => {
+ let n = Math.ceil(Math.log(num * Math.sqrt(5) + 1/2) / Math.log((Math.sqrt(5)+1)/2));
+ return Array.from({ length: n}).reduce((acc, val, i) => acc.concat(i > 1 ? acc[i - 1] + acc[i - 2] : i), []);
+}
+// fibonacciUntilNum(15) -> [0,1,1,2,3,5,8,13]
+gcd
Calculates the greatest common divisor between two numbers.
Use recursion.
@@ -823,16 +937,16 @@ Otherwise, return the GCD of y and the remainder of the division
hammingDistance
Calculates the Hamming distance between two values.
-Use XOR operator (^) to find the bit difference between the two numbers, convert to binary string using toString(2).
+
Use XOR operator (^) to find the bit difference between the two numbers, convert to a binary string using toString(2).
Count and return the number of 1s in the string, using match(/1/g).
const hammingDistance = (num1, num2) =>
((num1 ^ num2).toString(2).match(/1/g) || '').length;
// hammingDistance(2,3) -> 1
inRange
Checks if the given number falls in the given range.
+Checks if the given number falls within the given range.
Use arithmetic comparison to check if the given number is in the specified range.
-If the second parameter, end, is not specified, the reange is considered to be from 0 to start.
end, is not specified, the range is considered to be from 0 to start.
const inRange = (n, start, end=null) => {
if(end && start > end) end = [start, start=end][0];
return (end == null) ? (n>=0 && n<start) : (n>=start && n<end);
@@ -843,8 +957,8 @@ If the second parameter, end, is not specified, the reange is consi
// inrange(3, 2) -> false
isArmstrongNumber
Checks if the given number is an armstrong number or not.
-Convert the given number into array of digits. Use Math.pow() to get the appropriate power for each digit and sum them up. If the sum is equal to the number itself, return true otherwise false.
Checks if the given number is an Armstrong number or not.
+Convert the given number into an array of digits. Use Math.pow() to get the appropriate power for each digit and sum them up. If the sum is equal to the number itself, return true otherwise false.
const isArmstrongNumber = digits =>
( arr => arr.reduce( ( a, d ) => a + Math.pow( parseInt( d ), arr.length ), 0 ) == digits ? true : false )( ( digits+'' ).split( '' ) );
// isArmstrongNumber(1634) -> true
@@ -1008,7 +1122,7 @@ console.log(arr) // -> ['line1', 'line2', 'line3']
Object
cleanObj
Removes any properties except the ones specified from a JSON object.
-Use Object.keys() method to loop over given json object and deleting keys that are not included in given array.
+
Use Object.keys() method to loop over given JSON object and deleting keys that are not included in given array.
Also if you give it a special key (childIndicator) it will search deeply inside it to apply function to inner objects too.
const cleanObj = (obj, keysToKeep = [], childIndicator) => {
Object.keys(obj).forEach(key => {
@@ -1059,8 +1173,8 @@ orderby(users, ['name', 'age']) -> [{name: 'barney', age: 34}, {name: 'barney
*/
select
Retrieve a property that indicated by the selector from object.
-If property not exists returns undefined.
Retrieve a property that indicated by the selector from an object.
+If the property does not exists returns undefined.
const select = (from, selector) =>
selector.split('.').reduce((prev, cur) => prev && prev[cur], from);
@@ -1114,7 +1228,7 @@ Omit the lowerRest parameter to keep the rest of the string intact,
countVowels
Retuns number of vowels in provided string.
Use a regular expression to count number of vowels (A, E, I, O, U) in a string.
Use a regular expression to count the number of vowels (A, E, I, O, U) in a string.
const countVowels = str => (str.match(/[aeiou]/ig) || []).length;
// countVowels('foobar') -> 3
// countVowels('gym') -> 0
@@ -1127,7 +1241,7 @@ Omit the lowerRest parameter to keep the rest of the string intact,
fromCamelCase
Converts a string from camelcase.
-Use replace() to remove underscores, hyphens and spaces and convert words to camelcase.
+
Use replace() to remove underscores, hyphens, and spaces and convert words to camelcase.
Omit the second argument to use a default separator of _.
const fromCamelCase = (str, separator = '_') =>
str.replace(/([a-z\d])([A-Z])/g, '$1' + separator + '$2')
@@ -1136,6 +1250,15 @@ Omit the second argument to use a default separator of _.
// fromCamelCase('someLabelThatNeedsToBeCamelized', '-') -> 'some-label-that-needs-to-be-camelized'
// fromCamelCase('someJavascriptProperty', '_') -> 'some_javascript_property'
repeatString
Repeats a string n times using String.repeat()
If no string is provided the default is "" and the default number of times is 2.
const repeatString = (str="",num=2) => {
+ return num >= 0 ? str.repeat(num) : str;
+}
+// repeatString("abc",3) -> 'abcabcabc'
+// repeatString("abc") -> 'abcabc'
+reverseString
Reverses a string.
Use split('') and Array.reverse() to reverse the order of the characters in the string.
@@ -1152,7 +1275,7 @@ Combine characters to get a string using join('').
toCamelCase
Converts a string to camelcase.
-Use replace() to remove underscores, hyphens and spaces and convert words to camelcase.
Use replace() to remove underscores, hyphens, and spaces and convert words to camelcase.
const toCamelCase = str =>
str.replace(/^([A-Z])|[\s-_]+(\w)/g, (match, p1, p2, offset) => p2 ? p2.toUpperCase() : p1.toLowerCase());
// toCamelCase("some_database_field_name") -> 'someDatabaseFieldName'
@@ -1160,6 +1283,29 @@ Combine characters to get a string using join('').
// toCamelCase("some-javascript-property") -> 'someJavascriptProperty'
// toCamelCase("some-mixed_string with spaces_underscores-and-hyphens") -> 'someMixedStringWithSpacesUnderscoresAndHyphens'
toKebabCase
Converts a string to kebab case.
+Use replace() to add spaces before capital letters, convert toLowerCase(), then replace() underscores and spaces with hyphens.
+Also check if a string starts with a hyphen and remove it if yes.
const toKebabCase = str => {
+ str = str.replace(/([A-Z])/g," $1").toLowerCase().replace(/_/g,' ').replace(/-/g,' ').replace(/\s\s+/g, ' ').replace(/\s/g,'-');
+ return str.startsWith('-') ? str.slice(1,str.length) : str;
+}
+// toKebabCase("camelCase") -> 'camel-case'
+// toKebabCase("some text") -> 'some-text'
+// toKebabCase("some-mixed_string With spaces_underscores-and-hyphens") -> 'some-mixed-string-with-spaces-underscores-and-hyphens'
+// toKebabCase("AllThe-small Things") -> "all-the-small-things"
+toSnakeCase
Converts a string to snakecase.
+Use replace() to add underscores before capital letters, convert toLowerCase(), then replace() hyphens and spaces with underscores.
const toSnakeCase = str =>
+ str.replace(/(\w)([A-Z])/g, '$1_$2').replace(/[\s-_]+/g, '_').toLowerCase();
+// toSnakeCase("camelCase") -> 'camel_case'
+// toSnakeCase("some text") -> 'some_text'
+// toSnakeCase("some-javascript-property") -> 'some_javascript_property'
+// toSnakeCase("some-mixed_string With spaces_underscores-and-hyphens") -> 'some_mixed_string_with_spaces_underscores_and_hyphens'
+truncateString
Truncates a string up to a specified length.
Determine if the string's length is greater than num.
@@ -1170,7 +1316,7 @@ Return the string truncated to the desired length, with ... appende
words
Converts a given string into an array of words.
-Use String.split() with a supplied pattern (defaults to non alpha as a regex) to convert to an array of strings. Use Array.filter() to remove any empty strings.
+
Use String.split() with a supplied pattern (defaults to non-alpha as a regex) to convert to an array of strings. Use Array.filter() to remove any empty strings.
Omit the second argument to use the default regex.
const words = (str, pattern = /[^a-zA-Z-]+/) => str.split(pattern).filter(Boolean);
// words("I love javaScript!!") -> ["I", "love", "javaScript"]
@@ -1193,7 +1339,7 @@ Omit the second argument to use the default regex.
extendHex
Extends a 3-digit color code to a 6-digit color code.
Use Array.map(), split() and Array.join() to join the mapped array for converting a 3-digit RGB notated hexadecimal color-code to the 6-digit form.
-Array.slice() is used to remove # from string start since it's added once.
String.slice() is used to remove # from string start since it's added once.
const extendHex = shortHex =>
'#' + shortHex.slice(shortHex.startsWith('#') ? 1 : 0).split('').map(x => x+x).join('')
// extendHex('#03f') -> '#0033ff'
@@ -1208,7 +1354,7 @@ Omit the second argument to use the default regex.
hexToRGB
Converts a color code to a rgb() or rgba() string if alpha value is provided.
Use bitwise right-shift operator and mask bits with & (and) operator to convert a hexadecimal color code (with or without prefixed with #) to a string with the RGB values. If it's 3-digit color code, first convert to 6-digit version. If any alpha value is provided alongside 6-digit hex, give rgba() string in return.
Use bitwise right-shift operator and mask bits with & (and) operator to convert a hexadecimal color code (with or without prefixed with #) to a string with the RGB values. If it's 3-digit color code, first convert to 6-digit version. If an alpha value is provided alongside 6-digit hex, give rgba() string in return.
const hexToRGB = hex => {
let alpha = false, h = hex.slice(hex.startsWith('#') ? 1 : 0);
if (h.length === 3) h = [...h].map(x => x + x).join('');
@@ -1268,7 +1414,7 @@ Omit the second argument to use the default regex.
// isSymbol(Symbol('x')) -> true
RGBToHex
Converts the values of RGB components to a colorcode.
+Converts the values of RGB components to a color code.
Convert given RGB parameters to hexadecimal string using bitwise left-shift operator (<<) and toString(16), then padStart(6,'0') to get a 6-digit hexadecimal value.
const RGBToHex = (r, g, b) => ((r << 16) + (g << 8) + b).toString(16).padStart(6, '0');
// RGBToHex(255, 165, 1) -> 'ffa501'
@@ -1284,17 +1430,9 @@ Omit the second argument to use the default regex.
// (logged): timeTaken: 0.02099609375ms
toDecimalMark
Convert a float-point arithmetic to the Decimal mark form.
-Use toString() to convert the float num to a string, then use regex to separate every three characters of the integer part with a comma.
const toDecimalMark = (num) => {
- let cleanNum = num.toString().split('').filter(n => '0123456789.'.includes(n)).join('')
- let wholeNum = cleanNum.split('.')[0].replace(/\B(?=(\d{3})+(?!\d))/g, ",")
- let decNum = `.${cleanNum.split('.')[1]}`
- return wholeNum + decNum;
-}
-// toDecimalMark(12305030388.9087) //-> '12,305,030,388.9087'
-// toDecimalMark(123.889087e2) //-> '12,388.9087'
-// toDecimalMark('12305abc030388.9087') // -> '12,305,030,388.9087'
+Use toLocaleString() to convert a float-point arithmetic to the Decimal mark form. It makes a comma separated string from a number.
+const toDecimalMark = num => num.toLocaleString("en-US");
+// toDecimalMark(12305030388.9087) -> "12,305,030,388.9087"
toOrdinalSuffix
Adds an ordinal suffix to a number.
@@ -1326,6 +1464,21 @@ UseNumber() to check if the coercion holds.
const validateNumber = n => !isNaN(parseFloat(n)) && isFinite(n) && Number(n) == n;
// validateNumber('10') -> true
Uncategorized
+detectDeviceType
Detects wether the website is being opened in a mobile device or a desktop/laptop.
+Use a regular expression to test the navigator.userAgent property to figure out if the device is a mobile device or a desktop/laptop.
const detectDeviceType = () => /Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent) ? "Mobile" : "Desktop";
+// detectDeviceType() -> "Mobile"
+// detectDeviceType() -> "Desktop"
+negate
Negates a predicate function.
+Take a predicate function and apply not to it with its arguments.
const negate = func => (...args) => !fun(...args);
+// filter([1, 2, 3, 4, 5, 6], negate(isEven)) -> [1, 3, 5]
+// negate(isOdd)(1) -> false
+