fix: add result

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

v2/idiomatic/result/examples_create_test.go

@@ -0,0 +1,58 @@
+// 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 result
+
+import (
+	"fmt"
+
+	"github.com/IBM/fp-go/v2/errors"
+)
+
+func Example_creation() {
+	// Build an Either
+	leftValue, leftErr := Left[string](fmt.Errorf("some error"))
+	rightValue, rightErr := Right("value")
+
+	// Build from a value
+	fromNillable := FromNillable[string](fmt.Errorf("value was nil"))
+	leftFromNil, nilErr := fromNillable(nil)
+	value := "value"
+	rightFromPointer, ptrErr := fromNillable(&value)
+
+	// some predicate
+	isEven := func(num int) bool {
+		return num%2 == 0
+	}
+	fromEven := FromPredicate(isEven, errors.OnSome[int]("%d is an odd number"))
+	leftFromPred, predErrOdd := fromEven(3)
+	rightFromPred, predErrEven := fromEven(4)
+
+	fmt.Println(ToString(leftValue, leftErr))
+	fmt.Println(ToString(rightValue, rightErr))
+	fmt.Println(ToString(leftFromNil, nilErr))
+	fmt.Println(IsRight(rightFromPointer, ptrErr))
+	fmt.Println(ToString(leftFromPred, predErrOdd))
+	fmt.Println(ToString(rightFromPred, predErrEven))
+
+	// Output:
+	// Left(some error)
+	// Right[string](value)
+	// Left(value was nil)
+	// true
+	// Left(3 is an odd number)
+	// Right[int](4)
+
+}