task.md

Task

A Task makes it easy to model asynchronous operations that may fail, such as HTTP requests or reading/writing to files/databases.

Implements: Monad, Semigroup

• Task
  • Task(f)
  • Task.of(v)
  • Task.rejected(v)
  • Task.fork(reject, resolve)
  • Task.toString()
  • Task.map(f)
  • Task.getValue()
  • Task.ap(t)
  • Task.concat(t)
  • Task.chain(f)
  • Task.toPromise()

Task(f)

Task constructor.

Param	Type	Description
f	function	A function that takes two arguments: reject and resolve, which are functions. The function f normally initiates an asynchronous task or one that has side effects, and once it completes, it either calls the resolve function to resolve the task or rejects it.

Task.of(v)

Task constructor that creates a Task which immediately resolves.

Param	Type	Description
v	any	The value that is passed to the resolve function

Task.rejected(v)

Task constructor that creates a Task which immediately gets rejected.

Param	Type	Description
v	any	The value that is passed to the rejected function

Task.fork(reject, resolve)

Executes the Task.

Param	Type	Description
reject	function	Function to be called when the Task is rejected
resolve	function	Function to be called when the Task is resolved

Task.toString()

Gets a stringified version of the Task.

Task.map(f)

Applies the function f to the value of a successfully resolved Task.

Param	Type	Description
f	function	Function

Task.getValue()

Gets the function within the Task.

Task.ap(t)

Applies the successful value of the Task t to the successful value (a function) of the current Task.

Param	Type	Description
t	Task	Task with a function as the second element

Task.concat(t)

Concatenates the current Task with the passed one and returns a new Task. When resolved, it will return the successful result of both tasks.

Param	Type	Description
t	Task	Task to concatenate

Task.chain(f)

Chains together many computations that return a Task.

Param	Type	Description
f	function	Function that returns another Task

Task.toPromise()

Converts the current Task to a Promise.