Graphics.UI.Threepenny.Editors.Validation

Simple helpers to perform validation of user input.

    -- update only if valid
    value <- accumB def updateIfValid userEdits

    -- collect validation warnings
    warnings <- stepper ok validate userEdits
  

Documentation

data ValidationResult

Instances

Show ValidationResult

Methods

showsPrec :: Int -> ValidationResult -> ShowS

show :: ValidationResult -> String

showList :: [ValidationResult] -> ShowS

ok :: ValidationResult

All is good

fromWarnings :: [String] -> ValidationResult

Create a validation result from a list of warnings.

fromWarnings [] = ok

getWarnings :: ValidationResult -> [String]

class Validable a where

The class of values that support validation.

Minimal complete definition

validate

Methods

validate :: a -> ValidationResult

isValid :: Validable a => a -> Bool

updateIfValid :: Validable a => a -> a -> a