Lodash cheatsheet
Excerpt
This is not a complete list. · One-page guide to Lodash
#Collections
Finding
_.filter(list, (n) => n % 2)
_.find(list, (n) => n % 2)
_.findLast(list, ...)
Works for both arrays and objects.
Accessing
_.at([ abcd ], 0)
_.at([ abcd ], [ 0, 1 ])
Set/get
_.set(object, 'users[0].name', value)
_.get(object, 'users[0].name')
_.get(object, ['users', 0, 'name'])
Iteration
_.forEach(list, (item, i) => ...)
_.forEachRight(list, ...)
_.map(list, ...)
_.every(users, (u) => u.active)
_.any(users, ...)
#Array
Arrays
_.chunk([ abcd ], 2)
_.compact(list)
_.fill(Array(4), 'x')
_.flatten
_.flattenDeep
Filtering
_.drop([ abcdef ], 2)
_.dropRight([ abcdef ], 2)
_.take([ abcdef ], 2)
_.takeRight([ abcdef ], 2)
_.slice([ abcdef ], 2, 4)
_.initial([ abcdef ])
_.rest([ abcdef ])
_.dropWhile(list, 'active')
_.dropWhile(list, 'active', true)
_.dropWhile(list, { active: true })
_.dropWhile(list, (n) => ...)
_.dropRightWhile(list, ...)
_.without([ abcde ], b)
_.remove(list, (n) => n % 2)
Accessing
_.first([ abcdef ])
_.last([ abcdef ])
Sets
_.uniq()
_.difference([ abc ], [ bc ])
_.intersection([ abc ], [ bcd ])
_.union([ abc ], [ bcd ])
Indexes
_.findIndex(list, fn)
_.findLastIndex(list, fn)
_.sortedIndex(list, val)
_.sortedLastIndex(list, val)
#Functions
Currying
greet = (greeting, name) => `${greeting}, ${name}!`
fn = _.partial(fn, 'hi')
fn('joe')
fn = _.partial(fn, 'joe')
fn('yo')
_.curry(greet)('hi')
_.curryRight(greet)('joe')
#Decorating functions
Throttling
_.throttle(fn)
_.debounce(fn)
Limiting
_.before(5, fn)
_.after(5, fn)
_.once(fn)
Etc
_.wrap(_.escape, (name) => `hi ${name}`)
_.delay(fn, 2000)
_.negate(fn)
_.memoize(fn)
_.memoize(fn, ...)
#Strings
Capitalization
_.capitalize('hello world')
_.startCase('hello_world')
_.snakeCase('hello world')
_.kebabCase('hello world')
_.camelCase('hello world')
Padding
_.pad('abc', 3)
_.pad('abc', 8)
_.pad('abc', 8, '_-')
_.padStart('abc', 3)
_.padStart('abc', 6)
_.padStart('abc', 6, '_-')
_.padEnd('abc', 3)
_.padEnd('abc', 6)
_.padEnd('abc', 6, '_-')
Trim
_.trim(' str ')
_.trimLeft(' str ')
_.trimRight(' str ')
Etc
_.repeat('-', 2)
_.deburr('déjà vu')
_.trunc('hello world', 5)
_.startsWith('abc', 'a')
_.endsWith('abc', 'c')
#Objects
Keys and values
_.keys(obj)
_.values(obj)
#Chaining
Chain and value
_([1, 2, 3])
.reduce((total, n) => total + n)
.map((n) => n * n)
.tap(console.log)
.thru((n) => n.reverse())
.value()
