Improve strings.index_any and strings.last_index_any

core/strings/ascii_set.odin

@@ -0,0 +1,22 @@
+//+private
+package strings
+
+import "core:unicode/utf8"
+
+Ascii_Set :: distinct [8]u32;
+
+ascii_set_make :: proc(chars: string) -> (as: Ascii_Set, ok: bool) #no_bounds_check {
+	for i in 0..<len(chars) {
+		c := chars[i];
+		if c >= utf8.RUNE_SELF {
+			return;
+		}
+		as[c>>5] |= 1 << uint(c&31);
+	}
+	ok = true;
+	return;
+}
+
+ascii_set_contains :: proc(as: Ascii_Set, c: byte) -> bool #no_bounds_check {
+	return as[c>>5] & (1<<(c&31)) != 0;
+}