Simple number-printing utility function.

4271 -> "Four thousand two hundred seventy one"

Why?  Well, for one it permits the generation of larger
strings from simple 32-bit seed numbers.  This permits
sort of a "decompression" of string data from simple
inputs to do some fuzz testing or other things.

Utility/print_number.test/0.cc

@@ -0,0 +1,39 @@
+static_assert( __cplusplus > 2020'99 );
+
+#include "../print_number.h"
+
+#include <Alepha/Testing/TableTest.h>
+#include <Alepha/Testing/test.h>
+
+#include <Alepha/Utility/evaluation_helpers.h>
+
+static auto init= Alepha::Utility::enroll <=[]
+{
+	using namespace Alepha::Testing::exports;
+	"Do simple numerical tests come out as we want?"_test
+	<=TableTest< Alepha::Utility::formatPrint >::Cases
+	{
+		{ "zero", { 0 }, "zero" },
+		{ "one", { 1 }, "one" },
+		{ "seven hundred", { 700 }, "seven hundred" },
+		{ "one thousand twenty four", { 1024 }, "one thousand twenty four" },
+		{ "ten thousand two hundred forty", { 10240 }, "ten thousand two hundred forty" },
+		{ "1283721", { 1'283'721 }, "one million two hundred eighty three thousand seven hundred twenty one" },
+		{ "1000283000721", { 1'000'283'000'721 },
+				"one trillion two hundred eighty three million seven hundred twenty one" },
+
+		{ "1000283000721", { 1'000'283'000'000 },
+				"one trillion two hundred eighty three million" },
+	};
+
+	-"repl"_test <=[]
+	{
+		while( std::cin )
+		{
+			std::uint64_t value;
+			std::cout << "input: " << std::flush;
+			std::cin >> value;
+			std::cout << Alepha::Utility::formatPrint( value ) << std::endl;
+		}
+	};
+};

Utility/print_number.test/CMakeLists.txt

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+unit_test( 0 )