Return an Err errorMessage if the given value isn't float number, otherwise return Ok value.

import Validation exposing (Validator, ErrorMessage)


floatValidation : Validator String Float
floatValidation =
    isFloat "It is not float number!"


floatValidation "5.39161" -- Ok 5.39161
floatValidation "t.39161" -- Err "It is not float number!"

Return an Err errorMessage if the given value isn't positive float number, otherwise return Ok value. It contains also float validation of value.

Return an Err errorMessage if the given value isn't int number, otherwise return Ok value.

import Validation exposing (Validator, ErrorMessage)


intValidation : Validator String Int
intValidation =
    isInt "It is not int number!"


intValidation "108" -- Ok 108
intValidation "3.14" -- Err "It is not int number!"

Return an Err errorMessage if the given value isn't positive int number, otherwise return Ok value. It contains also int validation of value.

Return an Err errorMessage if the given string is empty, otherwise return Ok value.

Return an Err errorMessage if the given string isn't correct an email address, otherwise return Ok value.

Return an Err errorMessage if the given string isn't correct an url path, otherwise return Ok value.

Return an Err errorMessage if the given value isn't in list, otherwise return Ok value.

import Validation exposing (Validator, ErrorMessage)


elInListValidation : Validator (Int, List Int) Int
elInListValidation =
    isInList "Given value is not in list!"


elInListValidation (3, [1, 2, 3]) -- Ok 3
elInListValidation (5, [1, 2, 3]) -- Err "Given value is not in list!"

Return an Err errorMessage if the given boolean value is false, otherwise return Ok True.

Validate Field

Return an Err errorMessage if the given value of Field Valid a isn't same as validation argument, otherwise return Ok validation argument for others Validity or for Valid a is Ok value.

import Validation exposing (Validator, ErrorMessage, Field)


pass : Field String String
pass =
    Field "" (Valid "password*")


confirmPasswordValidation : Validator String String
confirmPasswordValidation =
    isEqualTo pass "The passwords don't match."


confirmPasswordValidation "password*" -- Ok password*
confirmPasswordValidation "pasword*"  -- Err "The passwords don't match."

Return false if Field hasn't validity Valid a, otherwise return true.

import Validation exposing (Field, field, preValidatedField)


intNotvalidValue = field "50"        -- Field "50" NotValidated
intValidValue = preValidatedField 50 -- Field "50" (Valid 50)


isValidField intNotvalidValue -- False
isValidField intValidValue    -- True