Module: `data.validation`¶

Stability:	3 - Stable
Bug Tracker:	https://github.com/folktale/data.validation/issues
Version:	1.3.0
Repository:	https://github.com/folktale/data.validation
Portability:	Portable
npm package:	`data.validation`

A disjunction that is more appropriate for validating inputs and aggregating failures.

Loading¶

Require the data.validation package, after installing it:

var Validation = require('data.validation')

This gives you back a data.validation.Validation object.

Why?¶

The Validation(α, β) is a disjunction that’s more appropriate for validating inputs, and aggregating failures. It’s isomorphic to data.either, but provides better terminology for these use cases (Failure and Success, versus Left and Right), and allows one to aggregate failures and successes as an Applicative Functor.

Additional resources¶

A Monad in Practicality: First-Class Failures — A tutorial showing how the Validation data structure can be used to model data validations.

Types and structures¶

Validation¶

class data.validation.Validation¶

type Validation(α, β) = Failure(α) | Success(β)

implements
  Applicative(β), Functor(β), Chain(β), Monad(β), ToString

Represents the logical disjunction between α and β.

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API Reference › Module: data.validation

Module: data.validation¶