wsgl parser: Add match() and expect() helpers
These will be used to simplify common parser patterns.
Bug: tint:282
Change-Id: Ia281b9aa66b98f4afc726e876fe8aeae5ff4f12c
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/31724
Commit-Queue: dan sinclair <dsinclair@chromium.org>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
diff --git a/src/reader/wgsl/parser_impl.h b/src/reader/wgsl/parser_impl.h
index eb0a77f..0cf0903 100644
--- a/src/reader/wgsl/parser_impl.h
+++ b/src/reader/wgsl/parser_impl.h
@@ -428,6 +428,42 @@
std::unique_ptr<ast::AssignmentStatement> assignment_stmt();
private:
+ /// @returns true and consumes the next token if it equals |tok|.
+ bool match(Token::Type tok);
+ /// Errors if the next token is not equal to |tok|.
+ /// Always consumes the next token.
+ /// @param use a description of what was being parsed if an error was raised.
+ /// @param tok the token to test against
+ /// @returns true if the next token equals |tok|.
+ bool expect(const std::string& use, Token::Type tok);
+ /// Parses a signed integer from the next token in the stream, erroring if the
+ /// next token is not a signed integer.
+ /// Always consumes the next token.
+ /// @param use a description of what was being parsed if an error was raised
+ /// @param out the pointer to write the parsed integer to
+ /// @returns true if the signed integer was parsed without error
+ bool expect_sint(const std::string& use, int32_t* out);
+ /// Parses a signed integer from the next token in the stream, erroring if
+ /// the next token is not a signed integer or is negative.
+ /// Always consumes the next token.
+ /// @param use a description of what was being parsed if an error was raised
+ /// @param out the pointer to write the parsed integer to
+ /// @returns true if the signed integer was parsed without error
+ bool expect_positive_sint(const std::string& use, uint32_t* out);
+ /// Parses a non-zero signed integer from the next token in the stream,
+ /// erroring if the next token is not a signed integer or is less than 1.
+ /// Always consumes the next token.
+ /// @param use a description of what was being parsed if an error was raised
+ /// @param out the pointer to write the parsed integer to
+ /// @returns true if the signed integer was parsed without error
+ bool expect_nonzero_positive_sint(const std::string& use, uint32_t* out);
+ /// Errors if the next token is not an identifier.
+ /// Always consumes the next token.
+ /// @param use a description of what was being parsed if an error was raised
+ /// @param out the pointer to write the parsed identifier to
+ /// @returns true if the identifier was parsed without error
+ bool expect_ident(const std::string& use, std::string* out);
+
ast::type::Type* type_decl_pointer(Token t);
ast::type::Type* type_decl_vector(Token t);
ast::type::Type* type_decl_array(Token t, ast::ArrayDecorationList decos);
