Treat radices >2^16 as large unless -l set

These radices are large enough that:
- there is no reason to use them as actual radices
- calculating them takes a lot of time!

Therefore, the exact MTC and radix type shouldn't be calculated by
default.  If you want to take the time, you still can with -l.  I am
keeping the original 2^32 limit even with -l, because the problem with
that is not performance, it is that the resulting MTC could overflow a
uint64 (also the CAN list only goes up to this range).

1 files changed, 6 insertions, 3 deletions

diff --git a/args.go b/args.go
index f2ede5d..99f4874 100644
--- a/args.go
+++ b/args.go
@@ -11,9 +11,10 @@ const ProgramVersion = "1.0.0-alpha+dev"
 
 // The arguments to this program
 type args struct {
-	Radix   uint
-	Compact bool
-	FullMap bool
+	Radix     uint
+	Compact   bool
+	FullMap   bool
+	LargeCalc bool
 	// If true, exit the program immediately after parsing args.
 	Exit bool
 }
@@ -24,6 +25,8 @@ func parseArgs() (args, error) {
 	flag.BoolVar(&a.FullMap, "f", false,
 		fmt.Sprintf("Show full digit map (up to %d) for every radix",
 			maxSmallRadix))
+	flag.BoolVar(&a.LargeCalc, "l", false,
+		"Calculate exact MTC and radix class for very large radices, which may take a while.")
 	help := flag.Bool("?", false,
 		"Get information about program usage then exit")
 	version := flag.Bool("V", false,