// Copyright (c) 2023 - 2025 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 reader import ( G "github.com/IBM/fp-go/v2/reader/generic" T "github.com/IBM/fp-go/v2/tuple" ) // SequenceT converts n inputs of higher kinded types into a higher kinded type of n strongly typed values, // represented as a tuple. This is useful for combining multiple independent Reader computations into a single // Reader that produces a tuple of all results. // SequenceT1 combines 1 Reader into a Reader of a 1-tuple. // // Example: // // type Config struct { Value int } // r := reader.Asks(func(c Config) int { return c.Value }) // result := reader.SequenceT1(r) // tuple := result(Config{Value: 42}) // Tuple1{F1: 42} func SequenceT1[R, A any](a Reader[R, A]) Reader[R, T.Tuple1[A]] { return G.SequenceT1[Reader[R, A], Reader[R, T.Tuple1[A]]](a) } // SequenceT2 combines 2 Readers into a Reader of a 2-tuple. // All Readers share the same environment and are evaluated with it. // // Example: // // type Config struct { X, Y int } // getX := reader.Asks(func(c Config) int { return c.X }) // getY := reader.Asks(func(c Config) int { return c.Y }) // result := reader.SequenceT2(getX, getY) // tuple := result(Config{X: 10, Y: 20}) // Tuple2{F1: 10, F2: 20} func SequenceT2[R, A, B any](a Reader[R, A], b Reader[R, B]) Reader[R, T.Tuple2[A, B]] { return G.SequenceT2[Reader[R, A], Reader[R, B], Reader[R, T.Tuple2[A, B]]](a, b) } // SequenceT3 combines 3 Readers into a Reader of a 3-tuple. // All Readers share the same environment and are evaluated with it. // // Example: // // type Config struct { Host string; Port int; Secure bool } // getHost := reader.Asks(func(c Config) string { return c.Host }) // getPort := reader.Asks(func(c Config) int { return c.Port }) // getSecure := reader.Asks(func(c Config) bool { return c.Secure }) // result := reader.SequenceT3(getHost, getPort, getSecure) // tuple := result(Config{Host: "localhost", Port: 8080, Secure: true}) // // Tuple3{F1: "localhost", F2: 8080, F3: true} func SequenceT3[R, A, B, C any](a Reader[R, A], b Reader[R, B], c Reader[R, C]) Reader[R, T.Tuple3[A, B, C]] { return G.SequenceT3[Reader[R, A], Reader[R, B], Reader[R, C], Reader[R, T.Tuple3[A, B, C]]](a, b, c) } // SequenceT4 combines 4 Readers into a Reader of a 4-tuple. // All Readers share the same environment and are evaluated with it. // // Example: // // type Config struct { A, B, C, D int } // getA := reader.Asks(func(c Config) int { return c.A }) // getB := reader.Asks(func(c Config) int { return c.B }) // getC := reader.Asks(func(c Config) int { return c.C }) // getD := reader.Asks(func(c Config) int { return c.D }) // result := reader.SequenceT4(getA, getB, getC, getD) // tuple := result(Config{A: 1, B: 2, C: 3, D: 4}) // // Tuple4{F1: 1, F2: 2, F3: 3, F4: 4} func SequenceT4[R, A, B, C, D any](a Reader[R, A], b Reader[R, B], c Reader[R, C], d Reader[R, D]) Reader[R, T.Tuple4[A, B, C, D]] { return G.SequenceT4[Reader[R, A], Reader[R, B], Reader[R, C], Reader[R, D], Reader[R, T.Tuple4[A, B, C, D]]](a, b, c, d) }