Config.Schema.Spec

This module provides a set of types and operations for defining configuration file schemas. These schemas can be built up using Applicative operations.

These specifications are suitable for be consumed by Config.Schema.Load and Config.Schema.Docs.

This is the schema system used by the glirc IRC client https://hackage.haskell.org/package/glirc. For a significant example, visit the Client.Configuration and Client.Configuration.Colors modules.

Specifying sections

data SectionSpecs a

A list of section specifications used to process a whole group of key-value pairs. Multiple section specifications can be combined using this type's Applicative instance.

Instances

Functor SectionSpecs

Methods

fmap :: (a -> b) -> SectionSpecs a -> SectionSpecs b

(<$) :: a -> SectionSpecs b -> SectionSpecs a

Applicative SectionSpecs

Methods

pure :: a -> SectionSpecs a

(<*>) :: SectionSpecs (a -> b) -> SectionSpecs a -> SectionSpecs b

(*>) :: SectionSpecs a -> SectionSpecs b -> SectionSpecs b

(<*) :: SectionSpecs a -> SectionSpecs b -> SectionSpecs a

reqSection

Arguments

:: Spec a

=> Text

section name

-> Text

description

-> SectionSpecs a

Specification for a required section with an implicit value specification.

optSection

Arguments

:: Spec a

=> Text

section name

-> Text

description

-> SectionSpecs (Maybe a)

Specification for an optional section with an implicit value specification.

reqSection'

Arguments

:: Text

section name

-> ValueSpecs a

value specification

-> Text

description

-> SectionSpecs a

Specification for a required section with an explicit value specification.

optSection'

Arguments

:: Text

section name

-> ValueSpecs a

value specification

-> Text

description

-> SectionSpecs (Maybe a)

Specification for an optional section with an explicit value specification.

Specifying values

data ValueSpecs a

Non-empty disjunction of value specifications. This type is the primary way to specify expected values. Use the Spec class to generate ValueSpecs for simple types.

Multiple specifications can be combined using this type's Alt instance.

Instances

Functor ValueSpecs

Methods

fmap :: (a -> b) -> ValueSpecs a -> ValueSpecs b

(<$) :: a -> ValueSpecs b -> ValueSpecs a

Alt ValueSpecs

Left-biased choice between two specifications

Methods

(<!>) :: ValueSpecs a -> ValueSpecs a -> ValueSpecs a

some :: Applicative ValueSpecs => ValueSpecs a -> ValueSpecs [a]

many :: Applicative ValueSpecs => ValueSpecs a -> ValueSpecs [a]

class Spec a where

Class of value specifications that don't require arguments.

Minimal complete definition

valuesSpec

Methods

valuesSpec :: ValueSpecs a

Instances

Spec Int

Methods

valuesSpec :: ValueSpecs Int

Spec Int8

Methods

valuesSpec :: ValueSpecs Int8

Spec Int16

Methods

valuesSpec :: ValueSpecs Int16

Spec Int32

Methods

valuesSpec :: ValueSpecs Int32

Spec Int64

Methods

valuesSpec :: ValueSpecs Int64

Spec Integer

Methods

valuesSpec :: ValueSpecs Integer

Spec Rational

Methods

valuesSpec :: ValueSpecs Rational

Spec Word

Methods

valuesSpec :: ValueSpecs Word

Spec Word8

Methods

valuesSpec :: ValueSpecs Word8

Spec Word16

Methods

valuesSpec :: ValueSpecs Word16

Spec Word32

Methods

valuesSpec :: ValueSpecs Word32

Spec Word64

Methods

valuesSpec :: ValueSpecs Word64

Spec Text

Methods

valuesSpec :: ValueSpecs Text

Spec a => Spec [a]

Methods

valuesSpec :: ValueSpecs [a]

(Spec a, Spec b) => Spec (Either a b)

Methods

valuesSpec :: ValueSpecs (Either a b)

sectionsSpec

Arguments

:: Text

unique documentation identifier

-> SectionSpecs a

underlying specification

-> ValueSpecs a

Named subsection value specification. The unique identifier will be used for generating a documentation section for this specification and should be unique within the scope of the specification being built.

assocSpec

Arguments

:: ValueSpecs a

underlying specification

-> ValueSpecs [(Text, a)]

Specification for a section list where the keys are user-defined. Values are matched against the underlying specification and returned as a list of section-name/value pairs.

Since: 0.3.0.0

atomSpec :: Text -> ValueSpecs ()

Specification for matching a particular atom.

anyAtomSpec :: ValueSpecs Text

Specification for matching any atom. Matched atom is returned.

listSpec :: ValueSpecs a -> ValueSpecs [a]

Specification for matching a list of values each satisfying a given element specification.

customSpec :: Text -> ValueSpecs a -> (a -> Maybe b) -> ValueSpecs b

The custom specification allows an arbitrary function to be used to validate the value extracted by a specification. If Nothing is returned the value is considered to have failed validation.

namedSpec

Arguments

:: Text

name

-> ValueSpecs a

underlying specification

-> ValueSpecs a

Named value specification. This is useful for factoring complicated value specifications out in the documentation to avoid repetition of complex specifications.

Derived specifications

oneOrList :: ValueSpecs a -> ValueSpecs [a]

Specification that matches either a single element or multiple elements in a list. This can be convenient for allowing the user to avoid having to specify singleton lists in the configuration file.

yesOrNoSpec :: ValueSpecs Bool

Specification for using yes and no to represent booleans True and False respectively

stringSpec :: ValueSpecs String

Specification for matching any text as a String

numSpec :: Num a => ValueSpecs a

Specification for matching any integral number.

fractionalSpec :: Fractional a => ValueSpecs a

Specification for matching any fractional number.

Since: 0.2.0.0

nonemptySpec :: ValueSpecs a -> ValueSpecs (NonEmpty a)

Matches a non-empty list.

Since: 0.2.0.0

oneOrNonemptySpec :: ValueSpecs a -> ValueSpecs (NonEmpty a)

Matches a single element or a non-empty list.

Since: 0.2.0.0

Executing specifications

runSections :: Applicative f => (forall x. SectionSpec x -> f x) -> SectionSpecs a -> f a

Given an function that handles a single, primitive section specification; runSections will generate one that processes a whole SectionsSpec.

The results from each section will be sequence together using the Applicative instance in of the result type, and the results can be indexed by the type parameter of the specification.

For an example use of runSections, see Config.Schema.Load.

runSections_ :: Monoid m => (forall x. SectionSpec x -> m) -> SectionSpecs a -> m

Given an function that handles a single, primitive section specification; runSections_ will generate one that processes a whole SectionsSpec.

The results from each section will be sequence together using the Monoid instance in of the result type, and the results will not be indexed by the type parameter of the specifications.

For an example use of runSections_, see Config.Schema.Docs.

runValueSpecs :: Alt f => (forall x. ValueSpec x -> f x) -> ValueSpecs a -> f a

Given an interpretation of a primitive value specification, extract a list of the possible interpretations of a disjunction of value specifications. Each of these primitive interpretations will be combined using the provided Alt instance.

runValueSpecs_ :: Semigroup m => (forall x. ValueSpec x -> m) -> ValueSpecs a -> m

Given an interpretation of a primitive value specification, extract a list of the possible interpretations of a disjunction of value specifications. Each of these primitive interpretations will be combined using the provided Semigroup instance.

Primitive specifications

data SectionSpec :: * -> * where

Specifications for single configuration sections.

The fields are section name, documentation text, value specification. Use ReqSection for required key-value pairs and OptSection for optional ones.

Constructors

ReqSection :: Text -> Text -> ValueSpecs a -> SectionSpec a

Required section: Name, Documentation, Specification

OptSection :: Text -> Text -> ValueSpecs a -> SectionSpec (Maybe a)

Optional section: Name, Documentation, Specification

liftSectionSpec :: SectionSpec a -> SectionSpecs a

Lift a single specification into a list of specifications.

Since: 0.2.0.0

data ValueSpec :: * -> * where

The primitive specification descriptions for values. Specifications built from these primitive cases are found in ValueSpecs.

Constructors

TextSpec :: ValueSpec Text

Matches any string literal

IntegerSpec :: ValueSpec Integer

Matches integral numbers

RationalSpec :: ValueSpec Rational

Matches any number

AnyAtomSpec :: ValueSpec Text

Matches any atom

AtomSpec :: Text -> ValueSpec ()

Specific atom to be matched

ListSpec :: ValueSpecs a -> ValueSpec [a]

Matches a list of the underlying specification

SectionSpecs :: Text -> SectionSpecs a -> ValueSpec a

Documentation identifier and section specification

AssocSpec :: ValueSpecs a -> ValueSpec [(Text, a)]

Matches an arbitrary list of sections. Similar to SectionSpec except that that the section names are user-defined.

CustomSpec :: Text -> ValueSpecs (Maybe a) -> ValueSpec a

Documentation text, underlying specification

NamedSpec :: Text -> ValueSpecs a -> ValueSpec a

Label used to hide complicated specs in documentation

liftValueSpec :: ValueSpec a -> ValueSpecs a

Lift a primitive value specification to ValueSpecs.

Since: 0.2.0.0