[MIRROR] improve randhex (#2943)

Co-authored-by: Spookerton <918997+Spookerton@users.noreply.github.com>

code/_helpers/text.dm

@@ -701,6 +701,18 @@
 			return "North-Northwest"
 
 
+/// Returns random hex of char length nibbles
+/proc/randhex(nibbles)
+	var/static/list/chars = list(
+		"0", "1", "2", "3", "4", "5", "6", "7",
+		"8", "9", "a", "b", "c", "d", "e", "f"
+	)
+	var/list/result = new (nibbles)
+	for (var/i = 1 to nibbles)
+		result[i] = chars[rand(1, 16)]
+	return jointext(result, "")
+
+
 /// Check if thing is an SUID. If other is supplied, check if other matches thing.
 /proc/is_suid(thing, other)
 	var/static/regex/suid_check = regex(@"^~[0-9a-zA-Z]{15}$")

code/_macros.dm

@@ -291,12 +291,6 @@
 #define num2hex(num) num2text(num, 1, 16)
 
 
-/// Generate random hex up to char length nibbles
-/proc/randhex(nibbles)
-	for (var/i = 1 to nibbles)
-		. += num2text(rand(0, 15), 1, 16)
-
-
 /// Increase the size of L by 1 at the end. Is the old last entry index.
 #define LIST_INC(L) ((L).len++)