Add recipe for haskell transformers.

Experimental recipe to see how packaging Haskell libraries goes.

dev-haskell/transformers/transformers-0.5.6.2.recipe

@@ -0,0 +1,59 @@
+SUMMARY="Concrete functor and monad transformers"
+DESCRIPTION="A portable library of functor and monad transformers, inspired \
+by the paper \"Functional Programming with Overloading and Higher-Order \
+Polymorphism\", by Mark P Jones, in Advanced School of Functional \
+Programming, 1995"
+HOMEPAGE="https://hackage.haskell.org/package/transformers"
+COPYRIGHT="2009-2020, Andy Gill, Ross Paterson"
+LICENSE="BSD (3-clause)"
+SOURCE_URI="https://hackage.haskell.org/package/transformers-$portVersion/transformers-$portVersion.tar.gz"
+CHECKSUM_SHA256="b668795d600297e4c8a7fd55a107b9827b2c52c0bc14c5ea0d65e20e6691c66c"
+REVISION="1"
+
+ARCHITECTURES="!x86_gcc2"
+SECONDARY_ARCHITECTURES="x86"
+
+ghcversion=8.6.5
+
+PROVIDES="
+	transformers$secondaryArchSuffix = $portVersion
+	"
+REQUIRES="
+	haiku$secondaryArchSuffix
+	lib:libcharset$secondaryArchSuffix
+	lib:libgmp$secondaryArchSuffix
+	lib:libiconv$secondaryArchSuffix
+	lib:libHSbase_4.12.0.0_ghc$ghcversion$secondaryArchSuffix
+	lib:libHSghc_prim_0.5.3_ghc$ghcversion$secondaryArchSuffix
+	lib:libHSinteger_gmp_1.0.2.0_ghc$ghcversion$secondaryArchSuffix
+	"
+
+BUILD_REQUIRES="
+	haiku${secondaryArchSuffix}_devel
+	devel:libcharset$secondaryArchSuffix
+	devel:libgmp$secondaryArchSuffix
+	devel:libiconv$secondaryArchSuffix
+	"
+BUILD_PREREQUIRES="
+	cmd:sh
+	cmd:ghc_$ghcversion
+	cmd:gcc$secondaryArchSuffix
+	"
+
+BUILD()
+{
+	# Workaround for haikuporter bug #207
+	mkdir -p /system/settings/ghc
+	cp -r /system/lib/x86/ghc-*/package.conf.d /system/settings/ghc/
+
+	ghc-pkg check
+
+	ghc --make Setup -o Setup
+	./Setup configure --prefix=$prefix --libdir=$libDir
+	./Setup -v build
+}
+
+INSTALL()
+{
+	./Setup install
+}