template-helper

A small Haskell-module for extracting source code powered by Template Haskell.

functionExtractor

signature

functionExtractor :: String -> ExpQ -- ListE

usage

testFunctions = $(functionExtractor "^test")

example

fooFunctionsInFile = $(functionExtractor "^foo")
fooBar = "hej"
fooGoo = "nej"

is the same as

fooFunctionsInFile = [("fooBar", fooBar),("fooGoo", fooGoo)]
fooBar = "hej"
fooGoo = "nej"

functionExtractorMap

functionExtractorMap works like functionsExtractor but applies a function over all function-pairs.

This functions is useful if the common return type of the functions is a type class.

signature

functionExtractorMap :: String -> ExpQ -> ExpQ

example

secondTypeclassTest =
  do let expected = ["45", "88.8", "\"hej\""]
         actual = $(functionExtractorMap "^tc" [|\n f -> show f|] )
     expected @=? actual

tcInt :: Integer
tcInt = 45

tcDouble :: Double
tcDouble = 88.8

tcString :: String
tcString = "hej"

locationModule

signature

locationModule :: ExpQ -- LitE

usage

name = $(locationModule)

example

module Foo where
name = $(locationModule)

is the same as

module Foo where
name = "Foo"

Useful with splice ([|..|]).