zeelib / Exports
Utility library in TypeScript, with a focus on Node and FP utils and emphasis on not rewriting builtin features.
npm i zeelib
See the docs below for details (generated from types and comments). Example:
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[zeelib](README.md) / Exports- and
- average
- capitalizeFirstChar
- chunk
- clamp
- collapseNewlines
- collapseWhitespace
- collectBy
- combineRegex
- compose
- countIn
- curry
- debounce
- diff
- div
- drop
- dropWhile
- each
- escapeForRegex
- execute
- fileExists
- filter
- findIndices
- findPort
- flattenAndUniq
- flip
- fold
- getFreeDisk
- getFreeMemory
- getGlobal
- getHashFromDate
- getHashFromSystem
- getKeyByValue
- getLoadAverage
- getMemoryUsage
- getOrdinal
- getProjectRoot
- getRegexFlags
- getStdin
- getTerminalColumns
- getTerminalRows
- getTerminalSize
- getUserHome
- getUserShell
- greater
- groupBy
- has
- hasColor
- hasDuplicate
- head
- id
- init
- initials
- intersection
- is
- isArrayLike
- isBetween
- isBoolean
- isClass
- isDate
- isDefined
- isDirectory
- isEmpty
- isError
- isEven
- isFile
- isFloat
- isFunction
- isGenerator
- isGeneratorFunction
- isInstalled
- isInteger
- isJson
- isMap
- isNode
- isNull
- isNullOrUndefined
- isNumber
- isObject
- isOdd
- isPrimitive
- isPromise
- isRegExp
- isRoot
- isSemver
- isSet
- isString
- isSymLink
- isSymbol
- isUndefined
- isValidDate
- keep
- last
- len
- lesser
- lightenOrDarken
- lines
- mapObject
- memoize
- mzero
- objectToString
- once
- open
- pick
- pipe
- pluck
- product
- prompt
- range
- readJson
- reduce
- removeBOM
- replicate
- rgbToHex
- safeGet
- scaleToFit
- shuffle
- sleep
- sortBy
- sortObject
- span
- splitAt
- store
- stripAnsi
- sub
- sum
- tail
- take
- takeLast
- takeWhile
- tap
- touch
- truncate
- tryJson
- typeOf
- union
- uniq
- uniqBy
- unless
- unlines
- until
- unwords
- watch
- words
- writeJson
Ƭ AnyFn: (...args: any[]) => any
▸ (...args): any
| Name | Type |
|---|---|
...args |
any[] |
any
Ƭ AnyMap: Record<string, any>
Ƭ Cb: (error: c.ExecFileException | null, stdout: string | Buffer, stderr: string | Buffer) => void
▸ (error, stdout, stderr): void
| Name | Type |
|---|---|
error |
c.ExecFileException | null |
stdout |
string | Buffer |
stderr |
string | Buffer |
void
Ƭ ColMap: Record<string, (t: string) => string>
Ƭ F: (...args: any[]) => any
▸ (...args): any
| Name | Type |
|---|---|
...args |
any[] |
any
Ƭ Listener: (a: AnyMap, b: AnyMap) => any
▸ (a, b): any
| Name | Type |
|---|---|
a |
AnyMap |
b |
AnyMap |
any
Ƭ R: (...args: any[]) => Timer
▸ (...args): Timer
| Name | Type |
|---|---|
...args |
any[] |
Ƭ R: string | any[] | AnyMap
Ƭ Timer: NodeJS.Timeout | number | null
Ƭ Updater: (a: AnyMap) => AnyMap
▸ (a): AnyMap
| Name | Type |
|---|---|
a |
AnyMap |
• Const colorize: ColMap
▸ and<T>(a): boolean
Returns false if any in input array is false
| Name |
|---|
T |
| Name | Type |
|---|---|
a |
T[] |
boolean
Example
and([ 1, 2, 3 ]) // => true
and([ 1, 2, 3, false ]) // => false▸ average(xs): number
Averages a list of numbers
| Name | Type |
|---|---|
xs |
number[] |
number
Example
average([ 2, 4, 6, 8 ]) // => 5▸ capitalizeFirstChar(str): string
Capitalizes the first character of string
| Name | Type |
|---|---|
str |
string |
string
Example
capitalizeFirstChar('things and stuff') // => 'Things and stuff'▸ chunk<T>(arr, n): T[][]
Splits an array into chunks
| Name |
|---|
T |
| Name | Type |
|---|---|
arr |
T[] |
n |
number |
T[][]
Example
chunk([1, 2, 3, 4 ], 2) // => [ [ 1, 2 ], [ 3, 4 ] ]▸ clamp(val, min, max): number
Takes a number, min, and max If number is between min and max, returns number Otherwise returns min or max
| Name | Type |
|---|---|
val |
number |
min |
number |
max |
number |
number
Example
clamp(100, 0, 1000) // => 100
clamp(100, 101, 1000) // => 101
clamp(100, 0, 99) // => 00▸ collapseNewlines(str): string
Collapses multiple newlines to two
| Name | Type |
|---|---|
str |
string |
string
Example
collapseNewlines('\n\n\n\n') // => '\n\n'▸ collapseWhitespace(str): string
Collapses consecutive whitespace to a single space
| Name | Type |
|---|---|
str |
string |
string
Example
collapseWhitespace('a\n\r\t\nb') // => 'a b'▸ collectBy(p): (a: any[]) => AnyMap
Collect an an array of objects by string key cred: gh:uniqname
| Name | Type |
|---|---|
p |
string |
fn
▸ (a): AnyMap
| Name | Type |
|---|---|
a |
any[] |
Example
const data = [ { foo: 'a', bar: 'baz' }, { foo: 'b', bar: 'quux' }, { foo: 'a', bar: 'whatever' } ]
collectBy('foo')(data) // => { a: { foo: 'a', bar: 'whatever' }, b: { foo: 'b', bar: 'quux' } }▸ combineRegex(rs, opts?): RegExp
Combines regular expressions
| Name | Type | Default value |
|---|---|---|
rs |
RegExp[] |
undefined |
opts |
string |
'' |
RegExp
Example
combineRegex([/[a-z]/, /[0-9]], 'g') ==> /[a-z][0-9]/g▸ compose<T>(...fns): (t: T) => T
Right to left composition
| Name |
|---|
T |
| Name | Type |
|---|---|
...fns |
(t: T) => T[] |
fn
▸ (t): T
| Name | Type |
|---|---|
t |
T |
T
Example
const addOne = (a) => a + 1
const timesTwo = (a) => a * 2
compose(addOne, timesTwo)(2) // => 5▸ countIn<T>(el, ls): number
Find out how many of a given element is in an array or string.
| Name |
|---|
T |
| Name | Type |
|---|---|
el |
T |
ls |
string | T[] |
number
Example
countIn('a', 'abc') // => 1
countIn('a', [ 'a', 'b', 'c' ]) // => 1▸ curry<T>(fn): F
Takes a function and returns a function that takes any number of arguments
Produces a curried function
| Name |
|---|
T |
| Name | Type |
|---|---|
fn |
F |
Example
const addThree = (a, b, c) => a + b + c
curry(addThree)(1)(1)(1) // => 3▸ debounce(fn, ms): R
Simple debounce
| Name | Type |
|---|---|
fn |
(...args: any) => any |
ms |
number |
Example
debounce(() => console.log('hi'), 5000)▸ diff<T>(a, b): T[]
Diff two arrays
| Name |
|---|
T |
| Name | Type |
|---|---|
a |
T[] |
b |
T[] |
T[]
Example
diff([ 1, 2, 3 ], [ 2, 3 ]) // => [ 1 ]▸ div(ns): number
Divide any amount of numbers
| Name | Type |
|---|---|
ns |
number[] |
number
Example
div([ 4, 2, 1 ]) // => 2▸ drop<A>(n, arr): A[]
Like Haskell's drop
| Name |
|---|
A |
| Name | Type |
|---|---|
n |
number |
arr |
A[] |
A[]
Example
drop(2, [ 1, 2, 3 ]) // => 3▸ dropWhile<T>(pred, arr): T[]
The opposite of takeWhile:
takes a predicate and array and returns an
array of the elements that didn't pass the predicate
| Name |
|---|
T |
| Name | Type |
|---|---|
pred |
(x: T) => boolean |
arr |
T[] |
T[]
Example
dropWhile(lessThanThree, [ 1, 2, 3, 4 ]) // => [ 3, 4 ]▸ each<T>(xs, fn): Record<string, any> | T[]
Takes an array or object and a function, and runs the function on each element
| Name |
|---|
T |
| Name | Type |
|---|---|
xs |
string | any[] | Record<string, any> |
fn |
(a: any, b: string | number) => T |
Record<string, any> | T[]
Example
each([ 'a', 'b', 'c' ], id) // => 'a'▸ escapeForRegex(s?): string
| Name | Type | Default value |
|---|---|---|
s |
string |
'' |
string
Example
escapeForRegex('foo') // => foo
escapeForRegex('1 \\ {} []|') // => '1 \\\\ \{\} \\[\\]\\|'▸ execute(cmd): void
Like a standalone npm run that obeys npm bin
| Name | Type |
|---|---|
cmd |
string |
void
Example
execute('standard-format -w')▸ fileExists(filePath): Promise<boolean>
Returns bool based on if passed path exists
| Name | Type |
|---|---|
filePath |
string |
Promise<boolean>
Example
await fileExists('./foo') // => Promise<true>▸ filter<T>(fn, list): T[] | Record<string, T>
filter for array and object
| Name |
|---|
T |
| Name | Type |
|---|---|
fn |
(x: T, y: string | number) => boolean |
list |
string | AnyMap | T[] |
T[] | Record<string, T>
Example
filter(id, [ 1, 2 ]) // => [ 1, 2 ]
filter(lessThanThree, [ 1, 2, 3, 4 ]) // => [ 1, 2 ]
filter(lessThanThree, { a: 1, b: 4 }) // => { a: 1 }▸ findIndices(el, arr): number[]
Find all indices of an item in an array
| Name | Type |
|---|---|
el |
any |
arr |
any[] |
number[]
Example
findIndices(1, [ 1, 2, 1 ]) // => [ 0, 2 ]▸ findPort(port, cb): void
Find next open port
| Name | Type |
|---|---|
port |
number |
cb |
(x: null | Error, y?: number) => void |
void
Example
findPort(8000, (err, port) => console.log(`${port} is open`))▸ flattenAndUniq<T>(arr): T[]
Recursively flatten arrays then uniq what's left
| Name |
|---|
T |
| Name | Type |
|---|---|
arr |
T[] |
T[]
Example
flattenAndUniq([ 1, 2, 3, [ 1, 2, 3 ]]) // => [ 1, 2, 3 ]▸ flip(f): (...args: any[]) => any
Flips order of received arguments and calls f.
| Name | Type |
|---|---|
f |
(...xs: any[]) => any |
fn
▸ (...args): any
| Name | Type |
|---|---|
...args |
any[] |
any
Example
const minus = (a, b) => a - b
minus(2, 1) // => 1
flip(minus)(2, 1) // => -1▸ fold<T>(f, a): T
Applies f to first two items of list, then to next, etc.
| Name |
|---|
T |
| Name | Type |
|---|---|
f |
(x: T, y: T) => T |
a |
T[] |
T
Example
foldl1(increment, [ 1, 1, 1 ]) // => 3▸ getFreeDisk(): number
Get free disk space
number
Example
getFreeDisk()▸ getFreeMemory(): number
Get free memory
number
Example
getFreeMemory()▸ getGlobal(): undefined | typeof globalThis
Gets the global for your current context.
undefined | typeof globalThis
Example
getGlobal() // => window, global, whatever▸ getHashFromDate(): string
Returns a hash based on current timestamp
string
Example
getHashFromDate()▸ getHashFromSystem(): string
Get a md5 hash based on hostname, process.ppid, and date
string
Example
getHashFromSystem()▸ getKeyByValue(value, object): undefined | string
Get the key for a value
| Name | Type |
|---|---|
value |
any |
object |
AnyMap |
undefined | string
Example
getKeyByValue('bar', { foo: 'bar' }) // => 'foo'▸ getLoadAverage(): number
Get load average
number
Example
getLoadAverage()▸ getMemoryUsage(): number
Get memory usage
number
Example
getMemoryUsage()▸ getOrdinal(n): string
Adds ordinal onto integer
Works up to 999
| Name | Type |
|---|---|
n |
number |
string
Example
getOrdinal(1) // => '1st'▸ getProjectRoot(): string
Get project root
string
Example
getProjectRoot() // /path/to/project▸ getRegexFlags(r): string[]
Returns the flags for a given regular expression
| Name | Type |
|---|---|
r |
RegExp |
string[]
Example
getRegexFlags(/foo/ig) // => [ 'g', 'i' ]▸ getStdin(f): void
Get stdin and do something with it.
| Name | Type |
|---|---|
f |
(a: string) => void |
void
Example
getStdin((str) => {
console.log(str.split(''))
})▸ getTerminalColumns(): number
Get columns of current terminal
number
Example
getTerminalColumns()▸ getTerminalRows(): number
Get current terminal rows
number
Example
getTerminalRows()▸ getTerminalSize(): Size
Returns size of the current terminal
Example
getTerminalSize() // => { columns: number, rows: number }▸ getUserHome(): string
Get current user's home directory
string
Example
getUserHome() // => /home/z▸ getUserShell(): string
Get the current user's shell, or an empty string on shell-less platforms
string
Example
getUserShell()▸ greater(a, b): number
Get the greater of two numbers
| Name | Type |
|---|---|
a |
number |
b |
number |
number
Example
greater(1, 2) // => 2▸ groupBy(p): (a: any[]) => AnyMap
Collect an an array of objects by string key
| Name | Type |
|---|---|
p |
string |
fn
▸ (a): AnyMap
| Name | Type |
|---|---|
a |
any[] |
Example
const data = [ { foo: 'a', bar: 'baz' }, { foo: 'b', bar: 'quux' }, { foo: 'a', bar: 'whatever' } ]
groupBy('foo')(data) // => { a: { foo: 'a', bar: 'whatever' }, b: { foo: 'b', bar: 'quux' } }▸ has(p, o): boolean
See if an object has a property
| Name | Type |
|---|---|
p |
string |
o |
AnyMap |
boolean
Example
has('a' { b: 'c' }) // => false▸ hasColor(): boolean
Returns true if the current terminal supports color
boolean
Example
hasColor()▸ hasDuplicate<T>(arr): boolean
Returns true if an array has any duplicate elements
| Name |
|---|
T |
| Name | Type |
|---|---|
arr |
T[] |
boolean
Example
hasDuplicate([ 1, 1, 2 ]) // => true▸ head<T>(arr): T
First element
| Name |
|---|
T |
| Name | Type |
|---|---|
arr |
T[] |
T
Example
head([ 1, 2, 3 ]) // => 1▸ id<A>(a): A
id
| Name |
|---|
A |
| Name | Type |
|---|---|
a |
A |
A
Example
id(1) // => 1
id() // => undefined▸ init(arr): any[]
Returns all but the last item of an array
| Name | Type |
|---|---|
arr |
any[] |
any[]
Example
init([ 1, 2, 3 ]) // => [ 1, 2 ]▸ initials(str): string
Trims a string to just caps
| Name | Type |
|---|---|
str |
string |
string
Example
initials('Zac Anger') // => 'ZA'▸ intersection<T>(xs, ys): T[]
Get the intersection of two arrays
| Name |
|---|
T |
| Name | Type |
|---|---|
xs |
T[] |
ys |
T[] |
T[]
Example
intersection([ 1, 2 ], []) // => []
intersection([ 1, 2, 3 ], [1, 2]) // => [ 1, 2 ]▸ is(t, val): boolean
Returns true if the value is of the type
| Name | Type |
|---|---|
t |
string |
val |
any |
boolean
Example
is('number', 2) // => true▸ isArrayLike(v): boolean
Returns true if the passed value is array-like
| Name | Type |
|---|---|
v |
any |
boolean
Example
isArrayLike({}) // => false
isArrayLike([ 1, 2 ]) // => true▸ isBetween(a, b, mid): boolean
Returns true if the last parameter is before the first and second parameters
| Name | Type |
|---|---|
a |
number |
b |
number |
mid |
number |
boolean
Example
isBetween(1, 3, 2) // => true
isBetween(2, 1, 2) // => false▸ isBoolean(v): boolean
Returns true if the value is a boolean
| Name | Type |
|---|---|
v |
any |
boolean
Example
isBoolean(true) // => true▸ isClass(fn): boolean
Returns true if passed fn is an ES2015 class
| Name | Type |
|---|---|
fn |
() => any |
boolean
Example
isClass(noop) // => false▸ isDate(v): boolean
Returns true if the value is a date
| Name | Type |
|---|---|
v |
any |
boolean
Example
isDate(new Date()) // => true▸ isDefined(v): boolean
Returns true if the value is defined
| Name | Type |
|---|---|
v |
any |
boolean
Example
isDefined(null) // => true▸ isDirectory(filePath): Promise<boolean>
Returns true if the path is a directory
| Name | Type |
|---|---|
filePath |
string |
Promise<boolean>
Example
await isDirectory('.') // => true
await isDirectory('./fake-path') // => false▸ isEmpty(v): boolean
Returns true if the value is empty
| Name | Type |
|---|---|
v |
any |
boolean
Example
isEmpty('') // => true
isEmpty({}) // => true
isEmpty([]) // => true
isEmpty(null) // => true▸ isError(a): boolean
Returns true if value is an error
| Name | Type |
|---|---|
a |
any |
boolean
Example
isError(new Error()) // => true▸ isEven(n): boolean
Returns true if the number is even
| Name | Type |
|---|---|
n |
number |
boolean
Example
isEven(2) // => true▸ isFile(filePath): Promise<boolean>
Returns true if the path is a file
| Name | Type |
|---|---|
filePath |
string |
Promise<boolean>
Example
isFile('./README.md') // => true
isFile('.') // => false▸ isFloat(n): boolean
Returns true if the number is a float
| Name | Type |
|---|---|
n |
number |
boolean
Example
isFloat(2) // => false
isFloat(2.2) // => true▸ isFunction(v): boolean
Returns true if the value is a function
| Name | Type |
|---|---|
v |
any |
boolean
Example
const noop = () => {}
isFunction(2) // => false
isFunction(noop) // => true▸ isGenerator(v): boolean
Returns true if passed val is a generator
| Name | Type |
|---|---|
v |
any |
boolean
Example
isGenerator(2) // => false▸ isGeneratorFunction(v): boolean
Returns true if val is a generator function
| Name | Type |
|---|---|
v |
any |
boolean
Example
isGeneratorFunction(2) // => false▸ isInstalled(pkgName): boolean
Returns true if the passed node_module name is installed
| Name | Type |
|---|---|
pkgName |
string |
boolean
Example
isInstalled('zeelib') // => true▸ isInteger(v): boolean
Returns true if the value is an integer
| Name | Type |
|---|---|
v |
any |
boolean
Example
isInteger(2) // => true
isInteger(1.1) // => false▸ isJson(str): boolean
Returns true if the string is valid JSON
| Name | Type |
|---|---|
str |
string |
boolean
Example
isJson(JSON.stringify({ a: 'b' })) // => true▸ isMap(v): boolean
Returns true if value is a map
| Name | Type |
|---|---|
v |
any |
boolean
Example
isMap(new Map()) // => true▸ isNode(): boolean
Returns true if code is in Node
boolean
Example
isNode()▸ isNull(v): boolean
Returns true if the value is null
| Name | Type |
|---|---|
v |
any |
boolean
Example
isNull(null) // => true▸ isNullOrUndefined(v): boolean
Returns true if the value is null or undefined
| Name | Type |
|---|---|
v |
any |
boolean
Example
isNullOrUndefined(null) // => true▸ isNumber(v): boolean
Returns true if the value is a number and is not NaN
| Name | Type |
|---|---|
v |
any |
boolean
Example
isNumber(2) // => true
isNumber(NaN) // => false▸ isObject(v): boolean
Returns true if the value is an object
| Name | Type |
|---|---|
v |
any |
boolean
Example
isObject('asdf') // => false▸ isOdd(n): boolean
Returns true if the number is odd
| Name | Type |
|---|---|
n |
number |
boolean
Example
isOdd(1) // => true▸ isPrimitive(v): boolean
Returns true if value is a primitive
| Name | Type |
|---|---|
v |
any |
boolean
Example
isPrimitive(1) // => true▸ isPromise(a): boolean
Returns true if value is a promise
| Name | Type |
|---|---|
a |
any |
boolean
Example
isPromise(Promise.resolve())▸ isRegExp(v): boolean
Returns true if value is a RegExp
| Name | Type |
|---|---|
v |
any |
boolean
Example
isRegExp(/a/) // => true▸ isRoot(): boolean
Check if current process is running as root.
boolean
Example
isRoot() // => true▸ isSemver(v): boolean
Returns true if the provided string is a valid semantic version
| Name | Type |
|---|---|
v |
string |
boolean
Example
isSemver("0.0.0") // => true
isSemver("0.") // => false▸ isSet(v): boolean
Returns true if value is a set
| Name | Type |
|---|---|
v |
any |
boolean
Example
isSet(new Set()) // => true▸ isString(v): boolean
Returns true if value is a string
| Name | Type |
|---|---|
v |
any |
boolean
Example
isString('a') // => true▸ isSymLink(filePath): Promise<boolean>
Returns true if path is a symlink
| Name | Type |
|---|---|
filePath |
string |
Promise<boolean>
Example
isSymLink('.') // => false▸ isSymbol(a): boolean
Returns true if value is a symbol
| Name | Type |
|---|---|
a |
any |
boolean
Example
isSymbol(Symbol.for('foo')) // => true▸ isUndefined(v): boolean
Returns true if value is undefined
| Name | Type |
|---|---|
v |
any |
boolean
Example
isUndefined(undefined) // => true▸ isValidDate(d): boolean
Returns true if the passed object is a valid Date
| Name | Type |
|---|---|
d |
Date |
boolean
Example
isValidDate('1234') // => false▸ keep(x): R
Returns an array or object with all falsey values removed
| Name | Type |
|---|---|
x |
R |
Example
keep([ 'a', null, '', 2]) // => [ 'a', 2 ]
keep({ a: '', b: null, c: 2 }) // => { c: 2 }▸ last<A>(arr): A
Returns the last element of the array
| Name |
|---|
A |
| Name | Type |
|---|---|
arr |
A[] |
A
Example
last([ 1, 2, 3 ]) // => 3▸ len(val): number
Get length of element
Works for array, object, string, set, map, and function
| Name | Type |
|---|---|
val |
any |
number
Example
len('foo') // => 3
len([ 1, 2 ]) => 2
len((a, b) => a + b) // => 2▸ lesser(a, b): number
Returns the lesser of two numbers
| Name | Type |
|---|---|
a |
number |
b |
number |
number
Example
lesser(1, 2) // => 1▸ lightenOrDarken(col, amt): string
Lighten or darken a color
| Name | Type |
|---|---|
col |
string |
amt |
number |
string
Example
// lighten
const newCol = lightenOrDarken('#F06D06', 20)
// darken
const newCol = lightenOrDarken('#F06D06', -20)▸ lines(str): string[]
Split a string on lines
| Name | Type |
|---|---|
str |
string |
string[]
Example
lines('foo\nbar') // => [ 'foo', 'bar' ]▸ mapObject(f, o, ctx?): AnyMap
Map for objects
| Name | Type |
|---|---|
f |
(a: any, b: string, c: any) => any |
o |
AnyMap |
ctx |
any |
Example
const f = (a) => a + ' world'
const d = { a: 'hello', b: 'sup' }
mapObject(f, d) // => { a: 'hello world', b: 'sup world' }▸ memoize(fn): any
A simple memoizing util
| Name | Type |
|---|---|
fn |
any |
any
Example
memoize((a) => a) // => [Function]
memoize((a) => a)(1) // => 1▸ mzero(v?): any
Get monadic empty/zero value for a type
| Name | Type |
|---|---|
v? |
any |
any
Example
mzero(1) // =>
mzero([1]) // => []▸ objectToString(v): string
toString
| Name | Type |
|---|---|
v |
any |
string
Example
objectToString({}) // => '[object Object]'▸ once<U>(fn): (...args: U[]) => U
Only calls fn once; subsequent calls just return first val
| Name |
|---|
U |
| Name | Type |
|---|---|
fn |
<T>(...args: T[]) => T |
fn
▸ (...args): U
| Name | Type |
|---|---|
...args |
U[] |
U
Example
const o = once(id)
o(1) // => 1
o() // => 1
o(2) // => 1▸ open(args, opts, cb): void
Opens things. Works on Linux, Mac, and Windows
| Name | Type |
|---|---|
args |
string |
opts |
AnyMap |
cb |
Cb |
void
Example
open('http://zacanger.com')▸ pick(ks, o): AnyMap
pick
as it is in rambda (not ramda)
| Name | Type |
|---|---|
ks |
string | string[] |
o |
AnyMap |
Example
pick('a', { a: 'a', b: 'b' }) // => { a: 'a' }
pick([ 'a', 'b' ], { a: 'a', b: 'b', c: 'c' }) // => { a: 'a', b: 'b' }▸ pipe<T>(...fns): (data: T) => T
Left to right composition
| Name |
|---|
T |
| Name | Type |
|---|---|
...fns |
AnyFn[] |
fn
▸ (data): T
| Name | Type |
|---|---|
data |
T |
T
Example
const addOne = (a) => a + 1
const timesTwo = (a) => a * 2
pipe(addOne, timesTwo)(2) // => 6▸ pluck(key, arr): any[]
Simple pluck
| Name | Type |
|---|---|
key |
string |
arr |
any[] |
any[]
Example
pluck('a', [ { a: 'a' }, { a: 'b' } ]) // => [ 'a', 'b' ]▸ product(nums): number
Get the product of a list of numbers
| Name | Type |
|---|---|
nums |
number[] |
number
Example
product([ 1, 2, 3, 4 ]) // => 24▸ prompt(question): Promise<string>
Create a simple prompt for the terminal
| Name | Type |
|---|---|
question |
string |
Promise<string>
Example
const answer = await prompt('Do the thing')
if (answer.toLowercase() === 'y') { doTheThing() }▸ range(a, b, step?): number[]
Range function
Takes a start and and end, and a step (defaults to 1).
This is inclusive. That is:
1..10,2 == 0,2,4,6,8,10
| Name | Type | Default value |
|---|---|---|
a |
number |
undefined |
b |
number |
undefined |
step |
number |
1 |
number[]
Example
range(1, 4) // => [ 1, 2, 3, 4 ]
range(1, 10, 3) // => [ 1, 4, 7, 10 ]▸ readJson(file): Promise<any[] | AnyMap>
Read json file and parse it
| Name | Type |
|---|---|
file |
string |
Promise<any[] | AnyMap>
Example
const json = await readJson('./foo.json')▸ reduce<A, B>(fn, initialValue, data): B
Reduce
| Name |
|---|
A |
B |
| Name | Type |
|---|---|
fn |
(b: B, a: A) => B |
initialValue |
B |
data |
A[] |
B
Example
reduce((a, b) => a + b, 0, [ 1, 2, 3, 4 ]) // => 10▸ removeBOM(content): string
The same as what's in Node's module (see lib/internal/module).
Remove byte order marker. This catches EF BB BF (the UTF-8 BOM)
because the buffer-to-string conversion in fs.readFileSync()
translates it to FEFF, the UTF-16 BOM.
| Name | Type |
|---|---|
content |
string |
string
Example
removeBOM(someContent)▸ replicate<A>(n, p): A[]
Generates an array of the length of the first param, filled with the second param, calling the second param if it's a function
| Name |
|---|
A |
| Name | Type |
|---|---|
n |
number |
p |
A | (n: number, i: number) => A |
A[]
Example
replicate(3, 10) // => [ 10, 10, 10 ]
replicate(4, (a) => a + 1) // => [ 5, 5, 5, 5 ]▸ rgbToHex(r, g, b): string
Convert rgb to hex
| Name | Type |
|---|---|
r |
number |
g |
number |
b |
number |
string
Example
rgbToHex(255, 255, 255) // => '#ffffff'▸ safeGet<A>(path, fallback?): (obj: AnyMap) => undefined | null | A
Like _.get: takes an access string and an optional fallback,
then an object
| Name |
|---|
A |
| Name | Type |
|---|---|
path |
string |
fallback? |
A |
fn
▸ (obj): undefined | null | A
| Name | Type |
|---|---|
obj |
AnyMap |
undefined | null | A
Example
safeGet('a.b.c')({ a: { b: { c: 'd' } } }) // => 'd'
safeGet('a.b.e')({ a: { b: { c: 'd' } } }) // => undefined
safeGet('a.b.e', 'f')({ a: { b: { c: 'd' } } }) // => 'f'▸ scaleToFit(width, height, maxWidth?, maxHeight?): Object
Takes a width, height, maxWidth, and maxHeight
Returns an object that tells you the largest you can scale to
| Name | Type |
|---|---|
width |
number |
height |
number |
maxWidth? |
number |
maxHeight? |
number |
Object
| Name | Type |
|---|---|
height |
number |
width |
number |
Example
scaleToFit(1400, 1200, 2000, 200) // => { width: 233.33333333333331, height: 200 }▸ shuffle<A>(arr): A[]
Randomly shuffle items in array
| Name |
|---|
A |
| Name | Type |
|---|---|
arr |
A[] |
A[]
Example
shuffle([ 1, 2, 3, 4 ])▸ sleep(ms): Promise<void>
Simple sleep.
| Name | Type |
|---|---|
ms |
number |
Promise<void>
Example
const delay = await sleep(1000)
sleep(1000).then(doAThing)▸ sortBy<A>(f, xs): A[]
Takes a sort fn and an array
Returns a sorted array
| Name |
|---|
A |
| Name | Type |
|---|---|
f |
(a: A) => number |
xs |
A[] |
A[]
Example
const list = [ { id: 1 }, { id: 3 }, { id: 2 } ]
sortBy(({ id }) => id, list) // => [ { id: 1 }, { id: 2 }, { id: 3 } ]▸ sortObject(o): AnyMap
Sort an object (recursively)
| Name | Type |
|---|---|
o |
AnyMap |
Example
sortObject({ b: 'c', a: 'd' }) // => { a: 'd', b: 'c' }▸ span<A>(pred, arr): [A[], A[]]
Similar to takeWhile: returns a tuple
of all elements that pass predicate
and all elements that did not
| Name |
|---|
A |
| Name | Type |
|---|---|
pred |
(a: A) => boolean |
arr |
A[] |
[A[], A[]]
Example
span(lessThanThree, [ 1, 2, 3, 4 ]) // => [ [ 1, 2 ], [ 3, 4 ] ]▸ splitAt<A>(num, arr): [A[], A[]]
Like Haskell's splitAt
splitAt n xs returns a tuple xs prefix of length n and second element is remainder of list
| Name |
|---|
A |
| Name | Type |
|---|---|
num |
number |
arr |
A[] |
[A[], A[]]
Example
splitAt(1, [ [ 'a', 'b' ], 'c' ]) // => [ [ [ 'a', 'b' ] ], [ 'c' ] ]▸ store(state?): Store
A very simple store implementation (think Redux-like)
| Name | Type |
|---|---|
state |
AnyMap |
Example
const state = store()
state.subscribe((next, prev) => next.foo)
state.update({ foo: 'bar' })▸ stripAnsi(s?): string
Remove ANSI escapes from string
| Name | Type | Default value |
|---|---|---|
s |
string |
'' |
string
Example
stripAnsi(colorize.blue('hello')) // => 'hello'▸ sub(ns): number
Subtract any amount of numbers
| Name | Type |
|---|---|
ns |
number[] |
number
Example
sub([ 4, 3, 2, 1 ]) // => -2▸ sum(nums): number
Sum an array of numbers
| Name | Type |
|---|---|
nums |
number[] |
number
Example
sum([ 1, 2, 3, 4 ]) // => 10▸ tail<T>(arr): T[]
All elements except first
| Name |
|---|
T |
| Name | Type |
|---|---|
arr |
T[] |
T[]
Example
tail([ 1, 2, 3, 4 ]) // => [ 2, 3, 4 ]▸ take<A>(n, a): A[]
Like Haskell's take
| Name |
|---|
A |
| Name | Type |
|---|---|
n |
number |
a |
A[] |
A[]
Example
take(2, [ 1, 2, 3 ]) // => [ 1, 2 ]▸ takeLast<A>(num, arr): A[]
Takes the last n items of array
| Name |
|---|
A |
| Name | Type |
|---|---|
num |
number |
arr |
A[] |
A[]
Example
takeLast(2, [ 1, 2, 3, 4 ]) // => [ 3, 4 ]▸ takeWhile<A>(pred, arr): A[]
Returns elements that pass predicate, until failure (ignores matches after failure)
| Name |
|---|
A |
| Name | Type |
|---|---|
pred |
(a: A, n: number) => boolean |
arr |
A[] |
A[]
Example
takeWhile((x) => x < 3, [ 1, 2, 3, 4 ]) // => [ 1, 2 ]▸ tap(msg): <A>(a: A) => A
Log a value to console, and return that value
| Name | Type |
|---|---|
msg |
string |
fn
▸ <A>(a): A
| Name |
|---|
A |
| Name | Type |
|---|---|
a |
A |
A
Example
const logger = tap('This is the thing!')
logger(2) // => this is the thing 2 ; 2▸ touch(filePath, contents?): Promise<void>
Make a file if it doesn't exist already
| Name | Type | Default value |
|---|---|---|
filePath |
string |
undefined |
contents |
string |
'' |
Promise<void>
Example
touch('foo.txt')
touch('foo.txt', 'contentx')▸ truncate(str, limit, tail?): string
Truncate a string
| Name | Type | Default value |
|---|---|---|
str |
string |
undefined |
limit |
number |
undefined |
tail |
string |
'…' |
string
Example
truncate('asdf asdf asdf asdf', 4) // => 'asd…'
truncate('asdf asdf asdf asdf', 8, ' etc.') // => 'asd etc.'▸ tryJson<T>(o): AnyMap | T
Tries to parse JSON, if is JSON
| Name |
|---|
T |
| Name | Type |
|---|---|
o |
T |
AnyMap | T
Example
tryJson('[1,2]') // => [ 1, 2 ]
tryJson([ 1, 2 ]) // => [ 1, 2 ]▸ typeOf(a): string
Enhanced typeof
| Name | Type |
|---|---|
a |
any |
string
Example
typeOf('a') // => 'string'
typeOf(new Date()) // => 'date'▸ union<A>(...xs): A[]
Get the union of any amount of arrays
| Name |
|---|
A |
| Name | Type |
|---|---|
...xs |
A[][] |
A[]
Example
union([ 1, 2, 3 ], [ 2, 3, 4 ]) // => [ 1, 2, 3, 4 ]▸ uniq<A>(arr): A[]
Uniq an array
| Name |
|---|
A |
| Name | Type |
|---|---|
arr |
A[] |
A[]
Example
uniq([ 1, 1, 2, 3 ]) // => [ 1, 2, 3 ]▸ uniqBy(el, xs): AnyMap[]
Unique an array by a string key of objects in array Returns only the values of the passed key
| Name | Type |
|---|---|
el |
string |
xs |
AnyMap[] |
AnyMap[]
Example
const a = [ { foo: 'foo' }, { foo: 'bar' }, { foo: 'foo' } ]
uniqBy('foo', a) // => [ { foo: 'foo' }, { foo: 'bar' } ]▸ unless<A>(cond, fn): null | A
Call a function if the condition is falsey
| Name |
|---|
A |
| Name | Type |
|---|---|
cond |
boolean |
fn |
() => A |
null | A
Example
unless(() => true, false) // => true▸ unlines(arr): string
Join an array with lines
| Name | Type |
|---|---|
arr |
string[] |
string
Example
unlines([ 'foo', 'bar' ]) // => 'foo\nbar'▸ until<T>(p, f): (...args: T[]) => T
Until p f yields result of applying f until p holds
| Name |
|---|
T |
| Name | Type |
|---|---|
p |
(x: T) => boolean |
f |
(...args: T[]) => T |
fn
▸ (...args): T
| Name | Type |
|---|---|
...args |
T[] |
T
Example
until(equals5, increment)(2) // => 5▸ unwords(arr): string
Join an array with spaces
| Name | Type |
|---|---|
arr |
string[] |
string
Example
unwords([ 'foo', bar ]) // => 'foo bar'▸ watch(filePath, cb): void
Watch a file for changes, and call the function
| Name | Type |
|---|---|
filePath |
string |
cb |
(event: string, filename: null | string) => void |
void
Example
watch('./foo', console.log)▸ words(str): string[]
Split a string on spaces
| Name | Type |
|---|---|
str |
string |
string[]
Example
words('foo bar') // => [ 'foo', 'bar' ]▸ writeJson(path, data, indent): Promise<void>
Write JSON from a stringifiable value
| Name | Type |
|---|---|
path |
string |
data |
any |
indent |
number |
Promise<void>
Example
await writeJson('foo.json', someObject, 4)