Yesod.Form.Core

Users of the forms library should not need to use this module in general. It is intended only for writing custom forms and form fields.

Documentation

data FormResult a

A form can produce three different results: there was no data available, the data was invalid, or there was a successful parse.

The Applicative instance will concatenate the failure messages in two FormResults.

Constructors

FormMissing

FormFailure [String]

FormSuccess a

Instances

Functor FormResult

Applicative FormResult

Show a => Show (FormResult a)

Monoid m => Monoid (FormResult m)

IsForm (GFormMonad s m (FormResult a, FieldInfo s m))

newtype GForm s m xml a

A generic form, allowing you to specifying the subsite datatype, master site datatype, a datatype for the form XML and the return type.

Constructors

GForm

Fields

deform :: FormInner s m (FormResult a, xml, Enctype)

Instances

Monoid xml => Functor (GForm sub url xml)

Monoid xml => Applicative (GForm sub url xml)

RunForm (GForm s m xml a)

newFormIdent :: Monad m => StateT Ints m String

Get a unique identifier.

deeperFormIdent :: Monad m => StateT Ints m ()

shallowerFormIdent :: Monad m => StateT Ints m ()

type Env = [(String, String)]

type FileEnv = [(String, FileInfo)]

data Enctype

The encoding type required by a form. The Show instance produces values that can be inserted directly into HTML.

Constructors

UrlEncoded

Multipart

Instances

Bounded Enctype

Enum Enctype

Eq Enctype

Monoid Enctype

ToHtml Enctype

data Ints

Constructors

IntCons Int Ints

IntSingle Int

Instances

Show Ints

requiredFieldHelper :: IsForm f => FieldProfile (FormSub f) (FormMaster f) (FormType f) -> FormFieldSettings -> Maybe (FormType f) -> f

Create a required field (ie, one that cannot be blank) from a FieldProfile.

optionalFieldHelper :: (IsForm f, Maybe b ~ FormType f) => FieldProfile (FormSub f) (FormMaster f) b -> FormFieldSettings -> Maybe (Maybe b) -> f

Create an optional field (ie, one that can be blank) from a FieldProfile.

fieldsToInput :: [FieldInfo sub y] -> [GWidget sub y ()]

mapFormXml :: (xml1 -> xml2) -> GForm s y xml1 a -> GForm s y xml2 a

Convert the XML in a GForm.

checkForm :: (a -> FormResult b) -> GForm s m x a -> GForm s m x b

Add a validation check to a form.

Note that if there is a validation error, this message will not automatically appear on the form; for that, you need to use checkField.

checkField :: (a -> Either String b) -> FormField s m a -> FormField s m b

Add a validation check to a FormField.

Unlike checkForm, the validation error will appear in the generated HTML of the form.

askParams :: Monad m => StateT Ints (ReaderT Env m) Env

askFiles :: Monad m => StateT Ints (ReaderT Env (ReaderT FileEnv m)) FileEnv

liftForm :: Monad m => m a -> StateT Ints (ReaderT Env (ReaderT FileEnv m)) a

class IsForm f where

Associated Types

type FormSub f

type FormMaster f

type FormType f

Methods

toForm :: FormInner (FormSub f) (FormMaster f) (FormResult (FormType f), FieldInfo (FormSub f) (FormMaster f), Enctype) -> f

Instances

IsForm (FormField s m a)

IsForm (GFormMonad s m (FormResult a, FieldInfo s m))

class RunForm f where

Associated Types

type RunFormSub f

type RunFormMaster f

type RunFormType f

Methods

runFormGeneric :: Env -> FileEnv -> f -> GHandler (RunFormSub f) (RunFormMaster f) (RunFormType f)

Instances

RunForm (GFormMonad s m a)

RunForm (GForm s m xml a)

type GFormMonad s m a = WriterT Enctype (FormInner s m) a

Data types

data FieldInfo sub y

Using this as the intermediate XML representation for fields allows us to write generic field functions and then different functions for producing actual HTML. See, for example, fieldsToTable and fieldsToPlain.

Constructors

FieldInfo

Fields

fiLabel :: Html

fiTooltip :: Html

fiIdent :: String

fiInput :: GWidget sub y ()

fiErrors :: Maybe Html

fiRequired :: Bool

Instances

IsForm (GFormMonad s m (FormResult a, FieldInfo s m))

data FormFieldSettings

Constructors

FormFieldSettings

Fields

ffsLabel :: String

ffsTooltip :: Html

ffsId :: Maybe String

ffsName :: Maybe String

Instances

IsString FormFieldSettings

data FieldProfile sub y a

A generic definition of a form field that can be used for generating both required and optional fields. See 'requiredFieldHelper and optionalFieldHelper.

Constructors

FieldProfile

Fields

fpParse :: String -> Either String a

fpRender :: a -> String

fpWidget :: String -> String -> String -> Bool -> GWidget sub y ()

ID, name, value, required

Type synonyms

type Form sub y = GForm sub y (GWidget sub y ())

type Formlet sub y a = Maybe a -> Form sub y a

type FormField sub y = GForm sub y [FieldInfo sub y]

type FormletField sub y a = Maybe a -> FormField sub y a

type FormInput sub y = GForm sub y [GWidget sub y ()]