deprecate perl version, make go version the new one (2.0.0)

util.go

@@ -0,0 +1,57 @@
+/*
+Copyright © 2023 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package main
+
+import "math"
+
+// find an item in a list
+func contains(s []string, e string) bool {
+	for _, a := range s {
+		if a == e {
+			return true
+		}
+	}
+	return false
+}
+
+func const2num(name string) float64 {
+	switch name {
+	case "Pi":
+		return math.Pi
+	case "Phi":
+		return math.Phi
+	case "Sqrt2":
+		return math.Sqrt2
+	case "SqrtE":
+		return math.SqrtE
+	case "SqrtPi":
+		return math.SqrtPi
+	case "SqrtPhi":
+		return math.SqrtPhi
+	case "Ln2":
+		return math.Ln2
+	case "Log2E":
+		return math.Log2E
+	case "Ln10":
+		return math.Ln10
+	case "Log10E":
+		return math.Log10E
+	default:
+		return 0
+	}
+}