unicode: export bidi details

unicode/ucd.ha

@@ -94,6 +94,39 @@ export fn gc_code(v: gc) const str = {
 	};
 };
 
+// Bidirectional classification.
+export type bidi = enum u8 {
+	UNKNOWN,
+	L,
+	LRE,
+	LRO,
+	R,
+	AL,
+	RLE,
+	RLO,
+	PDF,
+	EN,
+	ES,
+	ET,
+	AN,
+	CS,
+	NSM,
+	BN,
+	B,
+	S,
+	WS,
+	ON,
+	LRI,
+	RLI,
+	FSI,
+	PDI,
+};
+
+// Returns the [[bidi]] classification corresponding to this rune.
+export fn rune_bidi(rn: rune) bidi = {
+	return get_ucdrecord(rn).bidirectional: bidi;
+};
+
 // Unicode character Script attribute.
 export type script = enum u16 {
 	COMMON,			// Zyyy