Enumerable

Enumerable mixin.

users
  .map('friends')
  .select(function(u){ return u.age > 20 })
  .map('name.first')
  .grep(/^T/)

Installation

$ component install component/enumerable

API

• mixin()
• #each()
• #map()
• #select()
• #unique()
• #reject()
• #compact()
• #find()
• #findLast()
• #none()
• #any()
• #count()
• #indexOf()
• #has()
• #grep()
• #reduce()
• #max()
• #sum()
• #first()
• #last()
• #inGroupsOf()
• #at()
• #value()

mixin()

Mixin to obj.

 var Enumerable = require('enumerable');
 Enumerable(Something.prototype);

#each(fn:Function)

Iterate each value and invoke fn(val, i).

 users.each(function(val, i){
   
 })

#map(fn:Function)

Map each return value from fn(val, i).

Passing a callback function:

 users.map(function(user){
   return user.name.first
 })

Passing a property string:

 users.map('name.first')

#select(fn:Function|String)

Select all values that return a truthy value of fn(val, i).

 users.select(function(user){
   return user.age > 20
 })

With a property:

 items.select('complete')

#unique()

Select all unique values.

 nums.unique()

#reject(fn:Function|String|Mixed)

Reject all values that return a truthy value of fn(val, i).

Rejecting using a callback:

 users.reject(function(user){
   return user.age < 20
 })

Rejecting with a property:

 items.reject('complete')

Rejecting values via ==:

 data.reject(null)
 users.reject(tobi)

#compact()

Reject null and undefined.

 [1, null, 5, undefined].compact()
 // => [1,5]

#find(fn:Function)

Return the first value when fn(val, i) is truthy, otherwise return undefined.

 users.find(function(user){
   return user.role == 'admin'
 })

#findLast(fn:Function)

Return the last value when fn(val, i) is truthy, otherwise return undefined.

 users.findLast(function(user){
   return user.role == 'admin'
 })

#none(fn:Function|String)

Assert that none of the invocations of fn(val, i) are truthy.

For example ensuring that no pets are admins:

 pets.none(function(p){ return p.admin })
 pets.none('admin')

#any(fn:Function)

Assert that at least one invocation of fn(val, i) is truthy.

For example checking to see if any pets are ferrets:

 pets.any(function(pet){
   return pet.species == 'ferret'
 })

#count(fn:Function)

Count the number of times fn(val, i) returns true.

 var n = pets.count(function(pet){
   return pet.species == 'ferret'
 })

#indexOf(obj:Mixed)

Determine the indexof obj or return -1.

#has(obj:Mixed)

Check if obj is present in this enumerable.

#grep(re:RegExp)

Grep values using the given re.

 users.map('name').grep(/^tobi/i)

#reduce(fn:Function, [val]:Mixed)

Reduce with fn(accumulator, val, i) using optional init value defaulting to the first enumerable value.

#max(fn:Function|String)

Determine the max value.

With a callback function:

 pets.max(function(pet){
   return pet.age
 })

With property strings:

 pets.max('age')

With immediate values:

 nums.max()

#sum(fn:Function|String)

Determine the sum.

With a callback function:

 pets.sum(function(pet){
   return pet.age
 })

With property strings:

 pets.sum('age')

With immediate values:

 nums.sum()

#first([n]:Number|Function)

Return the first value, or first n values.

#last([n]:Number|Function)

Return the last value, or last n values.

#inGroupsOf(n:Number)

Return values in groups of n.

#at(i:Number)

Return the value at the given index.

#value()

Return the enumerable value.

License

MIT