initial checkin

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

option/number/number.go

@@ -0,0 +1,20 @@
+package number
+
+import (
+	"strconv"
+
+	F "github.com/ibm/fp-go/function"
+	O "github.com/ibm/fp-go/option"
+)
+
+func atoi(value string) (int, bool) {
+	data, err := strconv.Atoi(value)
+	return data, err == nil
+}
+
+var (
+	// Atoi converts a string to an integer
+	Atoi = O.Optionize1(atoi)
+	// Itoa converts an integer to a string
+	Itoa = F.Flow2(strconv.Itoa, O.Of[string])
+)