fix: auto generate SequenceT for ReaderIOEither

Signed-off-by: Dr. Carsten Leue <carsten.leue@de.ibm.com>

array/array.go

@@ -15,22 +15,13 @@ func From[A any](data ...A) []A {
 }
 
 // MakeBy returns a `Array` of length `n` with element `i` initialized with `f(i)`.
-func MakeBy[A any](n int, f func(int) A) []A {
-	// sanity check
-	if n <= 0 {
-		return Empty[A]()
-	}
-	// run the generator function across the input
-	as := make([]A, n)
-	for i := n - 1; i >= 0; i-- {
-		as[i] = f(i)
-	}
-	return as
+func MakeBy[F ~func(int) A, A any](n int, f F) []A {
+	return G.MakeBy[[]A](n, f)
 }
 
 // Replicate creates a `Array` containing a value repeated the specified number of times.
 func Replicate[A any](n int, a A) []A {
-	return MakeBy(n, F.Constant1[int](a))
+	return G.Replicate[[]A](n, a)
 }
 
 func MonadMap[A, B any](as []A, f func(a A) B) []B {
@@ -159,21 +150,19 @@ func Of[A any](a A) []A {
 }
 
 func MonadChain[A, B any](fa []A, f func(a A) []B) []B {
-	return array.Reduce(fa, func(bs []B, a A) []B {
-		return append(bs, f(a)...)
-	}, Zero[B]())
+	return G.MonadChain[[]A, []B](fa, f)
 }
 
-func Chain[A, B any](f func(a A) []B) func([]A) []B {
-	return F.Bind2nd(MonadChain[A, B], f)
+func Chain[A, B any](f func(A) []B) func([]A) []B {
+	return G.Chain[[]A, []B](f)
 }
 
 func MonadAp[B, A any](fab []func(A) B, fa []A) []B {
-	return MonadChain(fab, F.Bind1st(MonadMap[A, B], fa))
+	return G.MonadAp[[]B](fab, fa)
 }
 
 func Ap[B, A any](fa []A) func([]func(A) B) []B {
-	return F.Bind2nd(MonadAp[B, A], fa)
+	return G.Ap[[]B, []func(A) B](fa)
 }
 
 func Match[A, B any](onEmpty func() B, onNonEmpty func([]A) B) func([]A) B {

array/generic/array.go

@@ -17,6 +17,24 @@ func From[GA ~[]A, A any](data ...A) GA {
 	return data
 }
 
+// MakeBy returns a `Array` of length `n` with element `i` initialized with `f(i)`.
+func MakeBy[AS ~[]A, F ~func(int) A, A any](n int, f F) AS {
+	// sanity check
+	if n <= 0 {
+		return Empty[AS]()
+	}
+	// run the generator function across the input
+	as := make(AS, n)
+	for i := n - 1; i >= 0; i-- {
+		as[i] = f(i)
+	}
+	return as
+}
+
+func Replicate[AS ~[]A, A any](n int, a A) AS {
+	return MakeBy[AS](n, F.Constant1[int](a))
+}
+
 func Lookup[GA ~[]A, A any](idx int) func(GA) O.Option[A] {
 	none := O.None[A]()
 	if idx < 0 {
@@ -107,3 +125,21 @@ func MonadPartition[GA ~[]A, A any](as GA, pred func(A) bool) tuple.Tuple2[GA, G
 func Partition[GA ~[]A, A any](pred func(A) bool) func(GA) tuple.Tuple2[GA, GA] {
 	return F.Bind2nd(MonadPartition[GA, A], pred)
 }
+
+func MonadChain[AS ~[]A, BS ~[]B, A, B any](fa AS, f func(a A) BS) BS {
+	return array.Reduce(fa, func(bs BS, a A) BS {
+		return append(bs, f(a)...)
+	}, Empty[BS]())
+}
+
+func Chain[AS ~[]A, BS ~[]B, A, B any](f func(A) BS) func(AS) BS {
+	return F.Bind2nd(MonadChain[AS, BS, A, B], f)
+}
+
+func MonadAp[BS ~[]B, ABS ~[]func(A) B, AS ~[]A, B, A any](fab ABS, fa AS) BS {
+	return MonadChain(fab, F.Bind1st(MonadMap[AS, BS, A, B], fa))
+}
+
+func Ap[BS ~[]B, ABS ~[]func(A) B, AS ~[]A, B, A any](fa AS) func(ABS) BS {
+	return F.Bind2nd(MonadAp[BS, ABS, AS], fa)
+}

cli/contextreaderioeither.go

@@ -5,10 +5,118 @@ import (
 	"log"
 	"os"
 	"path/filepath"
+	"strings"
 
 	C "github.com/urfave/cli/v2"
 )
 
+func generateNestedCallbacks(i, total int) string {
+	var buf strings.Builder
+	for j := i; j < total; j++ {
+		if j > i {
+			buf.WriteString(" ")
+		}
+		buf.WriteString(fmt.Sprintf("func(T%d)", j+1))
+	}
+	if i > 0 {
+		buf.WriteString(" ")
+	}
+	buf.WriteString(tupleType(total))
+	return buf.String()
+}
+
+func generateContextReaderIOEitherSequenceT(f, fg *os.File, i int) {
+	// tuple type
+	tuple := tupleType(i)
+
+	// non-generic version
+	// generic version
+	fmt.Fprintf(f, "\n// SequenceT%d converts %d [ReaderIOEither] into a [ReaderIOEither] of a [T.Tuple%d].\n", i, i, i)
+	fmt.Fprintf(f, "func SequenceT%d[", i)
+	for j := 0; j < i; j++ {
+		if j > 0 {
+			fmt.Fprintf(f, ", ")
+		}
+		fmt.Fprintf(f, "T%d", j+1)
+	}
+	fmt.Fprintf(f, " any](")
+	for j := 0; j < i; j++ {
+		if j > 0 {
+			fmt.Fprintf(f, ", ")
+		}
+		fmt.Fprintf(f, "t%d ReaderIOEither[T%d]", j+1, j+1)
+	}
+	fmt.Fprintf(f, ") ReaderIOEither[%s] {\n", tuple)
+	fmt.Fprintf(f, "  return G.SequenceT%d[ReaderIOEither[%s]](", i, tuple)
+	for j := 0; j < i; j++ {
+		if j > 0 {
+			fmt.Fprintf(f, ", ")
+		}
+		fmt.Fprintf(f, "t%d", j+1)
+	}
+	fmt.Fprintf(f, ")\n")
+	fmt.Fprintf(f, "}\n")
+
+	// generic version
+	fmt.Fprintf(fg, "\n// SequenceT%d converts %d readers into a reader of a [T.Tuple%d].\n", i, i, i)
+	fmt.Fprintf(fg, "func SequenceT%d[\n", i)
+
+	fmt.Fprintf(fg, "  GR_TUPLE%d ~func(context.Context) GIO_TUPLE%d,\n", i, i)
+	for j := 0; j < i; j++ {
+		fmt.Fprintf(fg, "  GR_T%d ~func(context.Context) GIO_T%d,\n", j+1, j+1)
+	}
+
+	fmt.Fprintf(fg, "  GIO_TUPLE%d ~func() E.Either[error, %s],\n", i, tuple)
+	for j := 0; j < i; j++ {
+		fmt.Fprintf(fg, "  GIO_T%d ~func() E.Either[error, T%d],\n", j+1, j+1)
+	}
+
+	for j := 0; j < i; j++ {
+		fmt.Fprintf(fg, "  T%d", j+1)
+		if j < i-1 {
+			fmt.Fprintf(fg, ",\n")
+		}
+	}
+	fmt.Fprintf(fg, " any](\n")
+	for j := 0; j < i; j++ {
+		fmt.Fprintf(fg, "  t%d GR_T%d,\n", j+1, j+1)
+	}
+	fmt.Fprintf(fg, ") GR_TUPLE%d {\n", i)
+	fmt.Fprintf(fg, "  return A.SequenceT%d(\n", i)
+	// map call
+	var cr string
+	if i > 1 {
+		cb := generateNestedCallbacks(1, i)
+		cio := fmt.Sprintf("func() E.Either[error, %s]", cb)
+		cr = fmt.Sprintf("func(context.Context) %s", cio)
+	} else {
+		cr = fmt.Sprintf("GR_TUPLE%d", i)
+	}
+	fmt.Fprintf(fg, "    Map[GR_T%d, %s, GIO_T%d],\n", 1, cr, 1)
+	// the apply calls
+	for j := 1; j < i; j++ {
+		if j < i-1 {
+			cb := generateNestedCallbacks(j+1, i)
+			cio := fmt.Sprintf("func() E.Either[error, %s]", cb)
+			cr = fmt.Sprintf("func(context.Context) %s", cio)
+		} else {
+			cr = fmt.Sprintf("GR_TUPLE%d", i)
+		}
+		fmt.Fprintf(fg, "    Ap[%s, func(context.Context) func() E.Either[error, %s], GR_T%d],\n", cr, generateNestedCallbacks(j, i), j+1)
+	}
+	// raw parameters
+	for j := 0; j < i; j++ {
+		fmt.Fprintf(fg, "    t%d,\n", j+1)
+	}
+	// // map
+	// 	Ap[GB, func(E) func() ET.Either[L, func(C) T.Tuple3[A, B, C]], func(E) func() ET.Either[L, func(B) func(C) T.Tuple3[A, B, C]], GIOB, func() ET.Either[L, func(C) T.Tuple3[A, B, C]], func() ET.Either[L, func(B) func(C) T.Tuple3[A, B, C]], E, L, B, func(C) T.Tuple3[A, B, C]],
+	// 	Ap[GC, GTABC, func(E) func() ET.Either[L, func(C) T.Tuple3[A, B, C]], GIOC, GIOTABC, func() ET.Either[L, func(C) T.Tuple3[A, B, C]], E, L, C, T.Tuple3[A, B, C]],
+
+	// 	a, b, c,
+	fmt.Fprintf(fg, " )\n")
+	fmt.Fprintf(fg, "}\n")
+}
+
 func generateContextReaderIOEitherEitherize(f, fg *os.File, i int) {
 	// non generic version
 	fmt.Fprintf(f, "\n// Eitherize%d converts a function with %d parameters returning a tuple into a function with %d parameters returning a [ReaderIOEither[R]]\n// The inverse function is [Uneitherize%d]\n", i, i, i, i)
@@ -90,6 +198,7 @@ import (
 	"context"
 
 	G "github.com/IBM/fp-go/context/%s/generic"
+	T "github.com/IBM/fp-go/tuple"
 )
 `, pkg)
 
@@ -101,6 +210,8 @@ import (
 
 	E "github.com/IBM/fp-go/either"
 	RE "github.com/IBM/fp-go/readerioeither/generic"
+	A "github.com/IBM/fp-go/internal/apply"
+	T "github.com/IBM/fp-go/tuple"
 )
 `)
 
@@ -109,6 +220,8 @@ import (
 	for i := 1; i <= count; i++ {
 		// eitherize
 		generateContextReaderIOEitherEitherize(f, fg, i)
+		// sequenceT
+		generateContextReaderIOEitherSequenceT(f, fg, i)
 	}
 
 	return nil

context/readerioeither/doc.go

@@ -1,4 +1,19 @@
-// Package readerioeither contains a version of [ReaderIOEither] that takes a golang [context.Context] as its context
+// Copyright (c) 2023 IBM Corp.
+// All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package readerioeither contains a version of [ReaderIOEither] that takes a golang [context.Context] as its context and that assumes the standard go error
 package readerioeither
 
 //go:generate go run ../.. contextreaderioeither --count 10 --filename gen.go