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readert

package
v2.10.2 Latest Latest
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This package is not in the latest version of its module.

 Go to latest Published: Oct 23, 2026 License: Apache-2.0 Imports: 9 Imported by: 0

Documentation

Index

Constants

This section is empty.

Variables

This section is empty.

Functions

func Ap 

func Ap[GEA ~func(E) HKTA, GEB ~func(E) HKTB, GEFAB ~func(E) HKTFAB, E, A, HKTA, HKTB, HKTFAB any](
	fap apply.ApType[HKTA, HKTB, HKTFAB],
	fa GEA) func(GEFAB) GEB

func ApplicativeMonoid added in v2.1.20 

func ApplicativeMonoid[R, A any](
	_of func(A) func(R) A,
	_map functor.MapType[A, func(A) A, func(R) A, func(R) func(A) A],
	_ap apply.ApType[func(R) A, func(R) A, func(R) func(A) A],

	m M.Monoid[A],
) M.Monoid[func(R) A]

ApplicativeMonoid lifts a Monoid[A] into a Monoid[Reader[R, A]]. This allows you to combine Readers that produce monoid values, with an empty/identity Reader.

The _of parameter is the Of operation (pure/return) for the Reader type. The _map and _ap parameters are the curried Map and Ap operations for the Reader type.

Example: 

type Config struct { Prefix string }
// Using the string concatenation monoid
stringMonoid := monoid.MakeMonoid(func(a, b string) string { return a + b }, "")
readerMonoid := readert.ApplicativeMonoid(
    reader.Of[Config, string],
    reader.Map[Config, string, func(string) string],
    reader.Ap[string, Config, string],
    stringMonoid,
)

r1 := reader.Asks(func(c Config) string { return c.Prefix })
r2 := reader.Of[Config]("hello")
combined := readerMonoid.Concat(r1, r2)
result := combined(Config{Prefix: ">> "}) // ">> hello"
empty := readerMonoid.Empty()(Config{Prefix: "any"}) // ""

func ApplySemigroup added in v2.1.20 

func ApplySemigroup[R, A any](
	_map functor.MapType[A, func(A) A, func(R) A, func(R) func(A) A],
	_ap apply.ApType[func(R) A, func(R) A, func(R) func(A) A],

	s S.Semigroup[A],
) S.Semigroup[func(R) A]

ApplySemigroup lifts a Semigroup[A] into a Semigroup[Reader[R, A]]. This allows you to combine two Readers that produce semigroup values by combining their results using the semigroup's concat operation.

The _map and _ap parameters are the curried Map and Ap operations for the Reader type, typically obtained from the reader package.

Example: 

type Config struct { Multiplier int }
// Using the additive semigroup for integers
intSemigroup := semigroup.MakeSemigroup(func(a, b int) int { return a + b })
readerSemigroup := readert.ApplySemigroup(
    reader.Map[Config, int, func(int) int],
    reader.Ap[int, Config, int],
    intSemigroup,
)

r1 := reader.Of[Config](5)
r2 := reader.Of[Config](3)
combined := readerSemigroup.Concat(r1, r2)
result := combined(Config{Multiplier: 1}) // 8

func Chain 

func Chain[GEA ~func(E) HKTA, GEB ~func(E) HKTB, A, E, HKTA, HKTB any](
	fchain chain.ChainType[A, HKTA, HKTB],
	f func(A) GEB,
) func(GEA) GEB

func ChainFirst added in v2.3.44 

func ChainFirst[GEA ~func(E) HKTA, GEB ~func(E) HKTB, A, E, HKTA, HKTB any](
	fchain chain.ChainFirstType[A, HKTA, HKTB],
	f func(A) GEB,
) func(GEA) GEA

func FromReader 

func FromReader[GA ~func(E) A, GEA ~func(E) HKTA, E, A, HKTA any](
	fof pointed.OfType[A, HKTA]) func(ma GA) GEA

func Map 

func Map[GEA ~func(E) HKTA, GEB ~func(E) HKTB, E, A, B, HKTA, HKTB any](
	fmap functor.MapType[A, B, HKTA, HKTB],
	f func(A) B,
) func(GEA) GEB

func MonadAp 

func MonadAp[GEA ~func(E) HKTA, GEB ~func(E) HKTB, GEFAB ~func(E) HKTFAB, E, A, HKTA, HKTB, HKTFAB any](fap func(HKTFAB, HKTA) HKTB, fab GEFAB, fa GEA) GEB

HKTFAB = HKT[func(A)B]

func MonadChain 

func MonadChain[GEA ~func(E) HKTA, GEB ~func(E) HKTB, A, E, HKTA, HKTB any](
	fchain chain.MonadChainType[A, HKTA, HKTB],
	ma GEA,
	f func(A) GEB,
) GEB

func MonadChainFirst added in v2.3.44 

func MonadChainFirst[GEA ~func(E) HKTA, GEB ~func(E) HKTB, A, E, HKTA, HKTB any](
	fchain chain.MonadChainFirstType[A, HKTA, HKTB],
	ma GEA,
	f func(A) GEB,
) GEA

func MonadFromReader 

func MonadFromReader[GA ~func(E) A, GEA ~func(E) HKTA, E, A, HKTA any](
	fof pointed.OfType[A, HKTA], ma GA) GEA

func MonadMap 

func MonadMap[GEA ~func(E) HKTA, GEB ~func(E) HKTB, E, A, B, HKTA, HKTB any](
	fmap func(HKTA, func(A) B) HKTB,
	fa GEA,
	f func(A) B,
) GEB

func MonadOf 

func MonadOf[GEA ~func(E) HKTA, E, A, HKTA any](fof pointed.OfType[A, HKTA], a A) GEA

func Sequence 

func Sequence[
	HKTR2HKTR1A ~func(R2) HKTR1HKTA,
	R1, R2, HKTR1HKTA, HKTA any](
	mchain func(func(func(R1) HKTA) HKTA) func(HKTR1HKTA) HKTA,
	ma HKTR2HKTR1A,
) func(R1) func(R2) HKTA

func SequenceReader 

func SequenceReader[
	HKTR2HKTR1A ~func(R2) HKTR1HKTA,
	R1, R2, A, HKTR1HKTA, HKTA any](
	mmap func(func(func(R1) A) A) func(HKTR1HKTA) HKTA,
	ma HKTR2HKTR1A,
) func(R1) func(R2) HKTA

func Traverse 

func Traverse[
	HKTR2A ~func(R2) HKTA,
	HKTR1B ~func(R1) HKTB,
	R1, R2, A, HKTR1HKTB, HKTA, HKTB any](
	mmap func(func(A) HKTR1B) func(HKTA) HKTR1HKTB,
	mchain func(func(func(R1) HKTB) HKTB) func(HKTR1HKTB) HKTB,
	f func(A) HKTR1B,
) func(HKTR2A) func(R1) func(R2) HKTB

func TraverseReader 

func TraverseReader[
	HKTR2A ~func(R2) HKTA,
	HKTR1B ~func(R1) B,
	R1, R2, A, B, HKTR1HKTB, HKTA, HKTB any](
	mmap1 func(func(A) HKTR1B) func(HKTA) HKTR1HKTB,
	mmap2 func(func(func(R1) B) B) func(HKTR1HKTB) HKTB,
	f func(A) HKTR1B,
) func(HKTR2A) func(R1) func(R2) HKTB

Types

This section is empty.

Source Files

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