[clang] [NFC][Clang][Preprocessor] Refine the implementation of isNextPPTokenOneOf (PR #145546)

[Yanzuo Liu via cfe-commits]

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@@ -101,11 +101,10 @@ class Token {
   /// "if (Tok.is(tok::l_brace)) {...}".
   bool is(tok::TokenKind K) const { return Kind == K; }
   bool isNot(tok::TokenKind K) const { return Kind != K; }
-  bool isOneOf(tok::TokenKind K1, tok::TokenKind K2) const {
-    return is(K1) || is(K2);
-  }
-  template <typename... Ts> bool isOneOf(tok::TokenKind K1, Ts... Ks) const {
-    return is(K1) || isOneOf(Ks...);
+  template <typename... Ts> bool isOneOf(Ts... Ks) const {
+    static_assert(sizeof...(Ts) > 0,
+                  "requires at least one tok::TokenKind specified");
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zwuis wrote:

Open question: Is `sizeof...(Ts) >= 2` better than `sizeof...(Ts) > 0`? Old `isOneOf` implementation requires at least two TokenKind.

https://github.com/llvm/llvm-project/pull/145546