| Safe Haskell | Safe |
|---|---|
| Language | Haskell98 |
Text.Reform.Backend
Description
This module contains two classes. FormInput is a class which is parameterized over the input type used to represent form data in different web frameworks. There should be one instance for each framework, such as Happstack, Snap, WAI, etc.
The FormError class is used to map error messages into an application specific error type.
- data CommonFormError input
- = InputMissing FormId
- | NoStringFound input
- | NoFileFound input
- | MultiFilesFound input
- | MultiStringsFound input
- | MissingDefaultValue
- commonFormErrorStr :: (input -> String) -> CommonFormError input -> String
- class FormError e where
- type ErrorInputType e
- commonFormError :: CommonFormError (ErrorInputType e) -> e
- class FormInput input where
- type FileType input
- getInputString :: (FormError error, ErrorInputType error ~ input) => input -> Either error String
- getInputStrings :: input -> [String]
- getInputText :: (FormError error, ErrorInputType error ~ input) => input -> Either error Text
- getInputTexts :: input -> [Text]
- getInputFile :: (FormError error, ErrorInputType error ~ input) => input -> Either error (FileType input)
Documentation
data CommonFormError input Source
an error type used to represent errors that are common to all backends
These errors should only occur if there is a bug in the reform-*
packages. Perhaps we should make them an Exception so that we can
get rid of the FormError class.
Constructors
| InputMissing FormId | |
| NoStringFound input | |
| NoFileFound input | |
| MultiFilesFound input | |
| MultiStringsFound input | |
| MissingDefaultValue |
Instances
| Eq input => Eq (CommonFormError input) Source | |
| Ord input => Ord (CommonFormError input) Source | |
| Show input => Show (CommonFormError input) Source |
Arguments
| :: (input -> String) | show |
| -> CommonFormError input | |
| -> String |
some default error messages for CommonFormError
class FormError e where Source
A Class to lift a CommonFormError into an application-specific error type
Associated Types
type ErrorInputType e Source
Methods
commonFormError :: CommonFormError (ErrorInputType e) -> e Source
class FormInput input where Source
Class which all backends should implement.
Minimal complete definition
Associated Types
input is here the type that is used to represent a value
uploaded by the client in the request.
Methods
getInputString :: (FormError error, ErrorInputType error ~ input) => input -> Either error String Source
Parse the input into a string. This is used for simple text fields among other things
getInputStrings :: input -> [String] Source
Should be implemented
getInputText :: (FormError error, ErrorInputType error ~ input) => input -> Either error Text Source
Parse the input value into Text
getInputTexts :: input -> [Text] Source
Can be overriden for efficiency concerns
getInputFile :: (FormError error, ErrorInputType error ~ input) => input -> Either error (FileType input) Source
Get a file descriptor for an uploaded file