Add Alpha and Symbol generation as 2 separate utility methods

README.md

@@ -27,6 +27,8 @@ func main() {
     // The following functions will generate 20 chars long passwords out of
     fmt.Print(pwgen.New(20, "ab"))       // a's and b's
     fmt.Print(pwgen.Num(20))             // numbers
+    fmt.Print(pwgen.Alpha(20))           // alphabets
+    fmt.Print(pwgen.Symbols(20))         // symbols
     fmt.Print(pwgen.AlphaNum(20))        // alphanumeric characters
     fmt.Print(pwgen.AlphaNumSymbols(20)) // alphanumeric characters and symbols
 }

pwgen.go

@@ -6,8 +6,10 @@ import (
 
 // Characters the password can contain
 var num = "0123456789"
-var alphaNum = num + "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
-var alphaNumSymbols = alphaNum + "_-?!.,@#$%^&*()=[]{}<>"
+var alpha = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+var symbols = "_-?!.,@#$%^&*()=[]{}<>"
+var alphaNum = num + alpha
+var alphaNumSymbols = alphaNum + symbols
 
 // New generates a random string of the given length out of the characters in char
 func New(length int, chars string) string {
@@ -26,6 +28,16 @@ func Num(length int) string {
 	return New(length, num)
 }
 
+// Alpha generates a random string of the given length out of alphabets
+func Alpha(length int) string {
+	return New(length, alpha)
+}
+
+// Symbols generates a random string of the given length out of symbols
+func Symbols(length int) string {
+	return New(length, symbols)
+}
+
 // AlphaNum generates a random string of the given length out of alphanumeric characters
 func AlphaNum(length int) string {
 	return New(length, alphaNum)

pwgen_test.go

@@ -22,6 +22,26 @@ func TestNum(t *testing.T) {
 	}
 }
 
+func TestAlpha(t *testing.T) {
+	var password string
+	for i := 1; i < 21; i++ {
+		password = Alpha(i)
+		if len(password) != i {
+			t.Errorf("Expected length %d, got %d\n", i, len(password))
+		}
+	}
+}
+
+func TestSymbols(t *testing.T) {
+	var password string
+	for i := 1; i < 21; i++ {
+		password = Symbols(i)
+		if len(password) != i {
+			t.Errorf("Expected length %d, got %d\n", i, len(password))
+		}
+	}
+}
+
 func TestAlphaNum(t *testing.T) {
 	var password string
 	for i := 1; i < 21; i++ {