mirror of
https://github.com/IBM/fp-go.git
synced 2025-11-23 22:14:53 +02:00
90 lines
2.1 KiB
Go
90 lines
2.1 KiB
Go
// 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 mostlyadequate
|
|
|
|
import (
|
|
"fmt"
|
|
"regexp"
|
|
|
|
A "github.com/IBM/fp-go/v2/array"
|
|
F "github.com/IBM/fp-go/v2/function"
|
|
"github.com/IBM/fp-go/v2/ioresult"
|
|
R "github.com/IBM/fp-go/v2/result"
|
|
S "github.com/IBM/fp-go/v2/string"
|
|
)
|
|
|
|
func findUserByID(id int) IOResult[Chapter08User] {
|
|
switch id {
|
|
case 1:
|
|
return ioresult.Of(albert08)
|
|
case 2:
|
|
return ioresult.Of(gary08)
|
|
case 3:
|
|
return ioresult.Of(theresa08)
|
|
default:
|
|
return ioresult.Left[Chapter08User](fmt.Errorf("user %d not found", id))
|
|
}
|
|
}
|
|
|
|
func Example_solution11A() {
|
|
// eitherToMaybe :: Either b a -> Maybe a
|
|
eitherToMaybe := R.ToOption[string]
|
|
|
|
fmt.Println(eitherToMaybe(R.Of("one eyed willy")))
|
|
fmt.Println(eitherToMaybe(R.Left[string](fmt.Errorf("some error"))))
|
|
|
|
// Output:
|
|
// Some[string](one eyed willy)
|
|
// None[string]
|
|
}
|
|
|
|
func Example_solution11B() {
|
|
findByNameID := F.Flow2(
|
|
findUserByID,
|
|
ioresult.Map(Chapter08User.getName),
|
|
)
|
|
|
|
fmt.Println(findByNameID(1)())
|
|
fmt.Println(findByNameID(2)())
|
|
fmt.Println(findByNameID(3)())
|
|
fmt.Println(findByNameID(4)())
|
|
|
|
// Output:
|
|
// Right[string](Albert)
|
|
// Right[string](Gary)
|
|
// Right[string](Theresa)
|
|
// Left[*errors.errorString](user 4 not found)
|
|
}
|
|
|
|
func Example_solution11C() {
|
|
// strToList :: String -> [Char
|
|
strToList := Split(regexp.MustCompile(``))
|
|
|
|
// listToStr :: [Char] -> String
|
|
listToStr := A.Intercalate(S.Monoid)("")
|
|
|
|
sortLetters := F.Flow3(
|
|
strToList,
|
|
A.Sort(S.Ord),
|
|
listToStr,
|
|
)
|
|
|
|
fmt.Println(sortLetters("sortme"))
|
|
|
|
// Output:
|
|
// emorst
|
|
}
|