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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"expandHashHash(): function-like macro not expanded when '(' is not adjacent (PAR-style indirection)","articleBody":"When `##` concatenation produces a function-like macro name but the argument list `(...)` is not immediately adjacent in the replacement text (hidden behind a secondary macro parameter), simplecpp aborts expansion and emits the concatenated token bare.\n\n## Reproducer\n\n```cpp\n#define PAR(a, ...) a __VA_ARGS__\n#define PREFIX_SCALAR(T, N) T N\n#define DISPATCH(kind, ...) PAR(PREFIX_ ## kind, (__VA_ARGS__))\nDISPATCH(SCALAR, int, x)\n```\n\nExpected: \n```\nint x\n```\nActual:\n```\n1:\n2:\n3:\n4: PREFIX_SCALAR ( int , x )\n```\n\n## Root cause\n\n`expandHashHash()` checks only `B-\u003enext-\u003eop == '('` immediately after the `##` result. In the PAR pattern, `B-\u003enext` is `,` (not `(`), so the function-like expansion is skipped.\n\n## Fix\n\nA forward-scan fallback in the `appendTokens` context (`expandResult==false`) walks ahead on the same line, skipping `,` separators and resolving named parameter tokens via `expandArg()`, until `(` is found.\n\nPR attached: https://github.com/cppcheck-opensource/simplecpp/pull/655","author":{"url":"https://github.com/paulafy6","@type":"Person","name":"paulafy6"},"datePublished":"2026-05-28T08:27:43.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/656/simplecpp/issues/656"}