Frame.Types

Description

Defines a homogenous collection of field types to interface typeless HTTP and HTML with the application and with HaskellDB

Synopsis

Documentation

module Database.HaskellDB.FieldType

type FieldName = String Source

Label for a specific field

data WrapperType Source

Heterogeneous type wrapper

Constructors

WrapString (Maybe Int) String	String wrapper
WrapInt Int	Int wrappr
WrapBool Bool	Bool wrapper
WrapError FieldType String	Type error (specific case of error)
WrapEmpty FieldType	Empty type

Instances

Show WrapperType
Binary WrapperType
Wrappable WrapperType

type Fields = Map FieldName WrapperType Source

Collection of heterogenous fields associated by FieldName

showField Source

Arguments

:: FieldName	Field name to look up
-> Fields	Fields to look in
-> String	String representation of field to return

Casts the FieldName in fields to string

purge Source

Arguments

:: DBInfo
-> Fields	Fields to purge
-> Fields	Purged fields

Purge non mandatory empty fields

class Wrappable a whereSource

Methods

wrap Source

Arguments

:: DBInfo	The database to check for the type
-> FieldName	Field name that represents this value
-> a	The value in question
-> WrapperType	The wrapped value

Function to wrap a value associated with a given FieldName

unwrap Source

Arguments

:: WrapperType	The wrapped type
-> a	The originally typed value

Function to unwrap a WrapperType to its original type

Instances

Wrappable Bool
Wrappable Int
Wrappable WrapperType
Wrappable [Char]
Show a => Wrappable (Maybe a)
Size n => Wrappable (BoundedList Char n)

wrapInt :: String -> WrapperType Source

Wrap a String representation of an Int

wrapBool :: String -> WrapperType Source

Wrap a String representation of a Bool

wrapError Source

Arguments

:: WrapperType	The wrapped type to check
-> String	Error message

Returns an error message if there has been a wrapping error

isMandatory :: DBInfo -> FieldName -> Maybe Bool Source

maybeUnwrap Source

Arguments

:: Maybe WrapperType	The potential wrapped type
-> WrapperType	Definitely a wrapped type (though perhaps an empty one)

A potential WrapperType is WrapEmpty if Nothing

fromList'Source

Arguments

:: DBInfo	Database to use for wrapping info
-> [(FieldName, String)]	List of pairs associating a field name to some `String` representation of a value
-> Map FieldName WrapperType	The map associating field names to wrapped types

Special version of fromList that also wraps fields as it goes

unwrapField :: Wrappable a => FieldName -> Fields -> Maybe aSource