Rerefined.Predicate.Common

Handy utilities for defining predicates.

Re-exports

module Rerefined.Predicate

proxy# :: forall {k} (a :: k). Proxy# a

Witness for an unboxed Proxy# value, which has no runtime representation.

data Builder

Thin wrapper over Buffer with a handy Semigroup instance.

>>> :set -XOverloadedStrings -XMagicHash
>>> fromText "foo" <> fromChar '_' <> fromAddr "bar"#
"foo_bar"

Remember: this is a strict builder, so on contrary to Data.Text.Lazy.Builder for optimal performance you should use strict left folds instead of lazy right ones.

Note that (similar to other builders) concatenation of Builders allocates thunks. This is to a certain extent mitigated by aggressive inlining, but it is faster to use Buffer directly.

Instances

IsString Builder

Defined in Data.Text.Builder.Linear

Methods

fromString :: String -> Builder

Monoid Builder

Defined in Data.Text.Builder.Linear

Methods

mempty :: Builder

mappend :: Builder -> Builder -> Builder

mconcat :: [Builder] -> Builder

Semigroup Builder

Defined in Data.Text.Builder.Linear

Methods

(<>) :: Builder -> Builder -> Builder

sconcat :: NonEmpty Builder -> Builder

stimes :: Integral b => b -> Builder -> Builder

Show Builder

Defined in Data.Text.Builder.Linear

Methods

showsPrec :: Int -> Builder -> ShowS

show :: Builder -> String

showList :: [Builder] -> ShowS

Predicate validation

validateFail :: forall p. (Predicate p, KnownPredicateName p) => Proxy# p -> Builder -> [RefineFailure] -> Maybe RefineFailure

Shortcut for returning a predicate validation failure.

validateBool :: forall p. (Predicate p, KnownPredicateName p) => Proxy# p -> Builder -> Bool -> Maybe RefineFailure

Shortcut for simply validating a Bool.