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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Consider masking definition of Rf_error()?","articleBody":"Somewhat related to a recent post on R-devel, some users will still try to use `Rf_error()` in C++ code using Rcpp. However, (as is documented) C++ destructors won't run when a longjmp occurs in cases like this. For example:\r\n\r\n`````\r\n#include \u003cRcpp.h\u003e\r\nusing namespace Rcpp;\r\n\r\nstruct A {\r\n    A() { Rprintf(\"A()\\n\"); }\r\n    ~A() { Rprintf(\"~A()\\n\"); }\r\n};\r\n\r\n// [[Rcpp::export]]\r\nSEXP uhoh() {\r\n    A a;\r\n    Rf_error(\"Oops!\");\r\n}\r\n\r\n/*** R\r\nuhoh()\r\n*/\r\n`````\r\n\r\nIn this example, `~A()` is never printed.\r\n\r\nWe could consider masking the definition of `Rf_error()` in these contexts. For example, something like:\r\n\r\n```\r\n#define Rf_error(...) \\\r\n    static_assert(false, \"Use of Rf_error() in C++ contexts is unwise: consider using Rcpp::stop() instead.\");\r\n```\r\n\r\nThere might also be a way to provide our own definition of `Rf_error()` that \"masks\" the version provided by R, but I wasn't able to find something immediately obvious.","author":{"url":"https://github.com/kevinushey","@type":"Person","name":"kevinushey"},"datePublished":"2023-01-31T00:48:26.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":25},"url":"https://github.com/1247/Rcpp/issues/1247"}