[util] Add unicode output to NumParse

apps/NumParse/NumParse.v3

@@ -33,7 +33,13 @@ def renderVal(vtype: Type, val: Val) {
 					}
 					if (v.val >= 0 || !x.signed) {
 						trace.tab().put_uleb32(bits).outln();
-						trace.tab().put_utf8(bits).outln();
+						if (Utf8.isValidCodepoint(bits)) {
+							trace.tab().put_utf8(bits).outln();
+							if (bits >= 32) trace.tab().put_unicode(bits).outln();
+						}
+						if (u7.?(bits)) {
+							trace.tab().put_ascii(u7.!(bits)).outln();
+						}
 					}
 				}
 				v: Box<long> => {
@@ -134,6 +140,22 @@ class TraceBuilder extends StringBuilder {
 			putx_8(utf8_buffer[i]);
 		}
 	}
+	def put_unicode(codepoint: u32) -> this {
+		puts("unicode: ");
+		var count = Utf8.encode(codepoint, utf8_buffer, 0);
+		putr(utf8_buffer[0 ... count]);
+	}
+	def put_ascii(val: u7) -> this {
+		puts("ascii: ");
+		match (byte.view(val)) {
+			'\r' => puts("\\r");
+			'\t' => puts("\\t");
+			'\n' => puts("\\n");
+			_ => {
+				if (val >= 32) putc(val);
+			}
+		}
+	}
 	def outln() -> this {
 		ln();
 		System.puts(extract());