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GHC 9.10.3 · lts/ghc-9.10.x · 248f8f0 · 2026-10-05

Modulehslua-packaging-2.3.1Haskell2010

HsLua.Packaging.Function

Marshaling and documenting Haskell functions.

5 types
25 values

Packagehslua-packaging-2.3.1
Exports30
LanguageHaskell2010
LicenceMIT
SourceFunction.hs

datadata DocumentedFunction e

Haskell equivallent to CFunction, i.e., function callable from Lua.

Constructors

DocumentedFunction
- callFunction :: LuaE e NumResults
- functionName :: Name
- functionDoc :: FunctionDoc

Creating documented functions

12 declarations

valuedefun :: Name -> a -> HsFnPrecursor e a

Begin wrapping a monadic Lua function such that it can be turned into a documented function exposable to Lua.

valuelambda :: a -> HsFnPrecursor e a

Just like defun, but uses an empty name for the documented function. Should be used when defining methods or operators.

valueapplyParameter

:: HsFnPrecursor e (a -> b)
-> Parameter e a
-> HsFnPrecursor e b

Partially apply a parameter.

valuereturnResult

Like returnResult, but returns only a single result.

valuereturnResults

Take a HaskellFunction precursor and convert it into a full HaskellFunction, using the given FunctionResults to return the result to Lua.

valuereturnResultsOnStack

:: HsFnPrecursor e (LuaE e NumResults)
-> Text
-> DocumentedFunction e

Take a HaskellFunction precursor and convert it into a full HaskellFunction, using the given FunctionResults to return the result to Lua.

valueupdateFunctionDescription

Updates the description of a Haskell function. Leaves the function unchanged if it has no documentation.

valueliftPure :: (a -> b) -> a -> LuaE e b

Turns a pure function into a monadic Lua function.

The resulting function is strict.

valueliftPure2 :: (a -> b -> c) -> a -> b -> LuaE e c

Turns a binary function into a Lua function.

The resulting function is strict in both its arguments.

valueliftPure3 :: (a -> b -> c -> d) -> a -> b -> c -> LuaE e d

Turns a ternary function into a Lua function.

The resulting function is strict in all of its arguments.

valueliftPure4 :: (a -> b -> c -> d -> e) -> a -> b -> c -> d -> LuaE err e

Turns a quarternary function into a Lua function.

The resulting function is strict in all of its arguments.

valueliftPure5

:: a -> b -> c -> d -> e -> f
-> a
-> b
-> c
-> d
-> e
-> LuaE err f

Turns a quinary function into a Lua function.

The resulting function is strict in all of its arguments.

Types

datadata Parameter e a

Function parameter.

Constructors

Parameter
- parameterPeeker :: Peeker e a
- parameterDoc :: ParameterDoc

datadata FunctionResult e a

Result of a call to a Haskell function.

Constructors

FunctionResult
- fnResultPusher :: Pusher e a
- fnResultDoc :: ResultValueDoc

typetype FunctionResults e a = [FunctionResult e a]

List of function results in the order in which they are returned in Lua.

Operators

value(###) :: (a -> HsFnPrecursor e a) -> a -> HsFnPrecursor e a

Like ($), but left associative.

value(<#>) :: HsFnPrecursor e (a -> b) -> Parameter e a -> HsFnPrecursor e b

Inline version of applyParameter.

value(=#>)

Inline version of returnResults.

value(=?>) :: HsFnPrecursor e (LuaE e NumResults) -> Text -> DocumentedFunction e

Return a flexible number of results that have been pushed by the function action.

value(#?) :: DocumentedFunction e -> Text -> DocumentedFunction e

Inline version of updateFunctionDescription.

Modifying functions

2 declarations

valuesetName :: Name -> DocumentedFunction e -> DocumentedFunction e

Renames a documented function.

valuesince :: DocumentedFunction e -> Version -> DocumentedFunction e

Sets the library version at which the function was introduced in its current form.

Pushing to Lua

1 declaration

valuepushDocumentedFunction :: LuaError e => DocumentedFunction e -> LuaE e ()

Pushes a documented Haskell function to the Lua stack, making it usable as a normal function in Lua. At the same time, the function docs are registered in the documentation table.

Convenience functions

4 declarations

valueparameter

:: Peeker e a
method to retrieve value from Lua
-> TypeSpec
expected Lua type
-> Text
parameter name
-> Text
parameter description
-> Parameter e a

Creates a parameter.

valueopt :: Parameter e a -> Parameter e (Maybe a)

Makes a parameter optional.

valueoptionalParameter

:: Peeker e a
method to retrieve the value from Lua
-> TypeSpec
expected Lua type
-> Text
parameter name
-> Text
parameter description
-> Parameter e (Maybe a)

Deprecated. Use `opt (parameter ...)` instead.

Creates an optional parameter.

DEPRECATED: Use opt (parameter ...) instead.

valuefunctionResult

:: Pusher e a
method to push the Haskell result to Lua
-> TypeSpec
Lua type of result
-> Text
result description
-> FunctionResults e a

Creates a function result.

Internal

2 declarations

datadata HsFnPrecursor e a

Helper type used to create HaskellFunctions.

Instances1Functor

Functor (HsFnPrecursor e)Defined in hslua-packaging-2.3.1 · HsLua.Packaging.Function

valuetoHsFnPrecursor :: StackIndex -> Name -> a -> HsFnPrecursor e a

Create a HaskellFunction precursor from a monadic function, selecting the stack index after which the first function parameter will be placed.