add support for non-scalar inputs

generate/util.go

@@ -0,0 +1,28 @@
+package generate
+
+import (
+	"unicode"
+	"unicode/utf8"
+)
+
+func reverse(slice []string) {
+	for left, right := 0, len(slice)-1; left < right; left, right = left+1, right-1 {
+		slice[left], slice[right] = slice[right], slice[left]
+	}
+}
+
+func changeFirst(s string, f func(rune) rune) string {
+	c, n := utf8.DecodeRuneInString(s)
+	if c == utf8.RuneError { // empty or invalid
+		return s
+	}
+	return string(f(c)) + s[n:]
+}
+
+func lowerFirst(s string) string {
+	return changeFirst(s, unicode.ToLower)
+}
+
+func upperFirst(s string) string {
+	return changeFirst(s, unicode.ToUpper)
+}