diff --git a/iterator/stateless/generic/io.go b/iterator/stateless/generic/io.go new file mode 100644 index 0000000..7287884 --- /dev/null +++ b/iterator/stateless/generic/io.go @@ -0,0 +1,34 @@ +// 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 generic + +import ( + F "github.com/IBM/fp-go/function" + L "github.com/IBM/fp-go/io/generic" + O "github.com/IBM/fp-go/option" + T "github.com/IBM/fp-go/tuple" +) + +// FromLazy returns an iterator on top of a lazy function +func FromLazy[GU ~func() O.Option[T.Tuple2[GU, U]], LZ ~func() U, U any](l LZ) GU { + return F.Pipe1( + l, + L.Map[LZ, GU](F.Flow2( + F.Bind1st(T.MakeTuple2[GU, U], Empty[GU]()), + O.Of[T.Tuple2[GU, U]], + )), + ) +} diff --git a/iterator/stateless/io.go b/iterator/stateless/io.go new file mode 100644 index 0000000..78d9d6f --- /dev/null +++ b/iterator/stateless/io.go @@ -0,0 +1,32 @@ +// 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 stateless + +import ( + IO "github.com/IBM/fp-go/io" + G "github.com/IBM/fp-go/iterator/stateless/generic" + L "github.com/IBM/fp-go/lazy" +) + +// FromLazy returns an [Iterator] on top of a lazy function +func FromLazy[U any](l L.Lazy[U]) Iterator[U] { + return G.FromLazy[Iterator[U], L.Lazy[U]](l) +} + +// FromIO returns an [Iterator] on top of an IO function +func FromIO[U any](io IO.IO[U]) Iterator[U] { + return G.FromLazy[Iterator[U], IO.IO[U]](io) +} diff --git a/iterator/stateless/io_test.go b/iterator/stateless/io_test.go new file mode 100644 index 0000000..693d071 --- /dev/null +++ b/iterator/stateless/io_test.go @@ -0,0 +1,38 @@ +// 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 stateless + +import ( + "math/rand" + "testing" + + "github.com/stretchr/testify/assert" +) + +func TestIteratorFromLazy(t *testing.T) { + num := rand.Int + + cit := FromLazy(num) + + // create arrays twice + c1 := ToArray(cit) + c2 := ToArray(cit) + + assert.Equal(t, 1, len(c1)) + assert.Equal(t, 1, len(c2)) + + assert.NotEqual(t, c1, c2) +}