{"record":{"id":"547569d0a2d6533b","repo":"diesel-rs/diesel","slug":"auto-type-tuple-type-and-its-expression-have-diff","errorCode":null,"errorMessage":"auto_type: tuple type and its expression have different number of elements","messagePattern":"auto_type: tuple type and its expression have different number of elements","errorType":"exception","errorClass":"syn::Error","httpStatus":null,"severity":"error","filePath":"dsl_auto_type/src/auto_type/expression_type_inference.rs","lineNumber":108,"sourceCode":"        ) {\n            (syn::Expr::Group(syn::ExprGroup { expr, .. }), type_hint) => {\n                return self.try_infer_expression_type(expr, type_hint);\n            }\n            (syn::Expr::Paren(syn::ExprParen { expr, .. }), type_hint) => {\n                return self.try_infer_expression_type(expr, type_hint);\n            }\n            (\n                syn::Expr::Tuple(syn::ExprTuple {\n                    elems: expr_elems, ..\n                }),\n                Some(syn::Type::Tuple(\n                    type_tuple @ syn::TypeTuple {\n                        elems: type_elems, ..\n                    },\n                )),\n            ) => {\n                if type_elems.len() != expr_elems.len() {\n                    return Err(syn::Error::new(\n                        type_tuple.span(),\n                        \"auto_type: tuple type and its \\\n                            expression have different number of elements\",\n                    ));\n                }\n                syn::Type::Tuple(syn::TypeTuple {\n                    elems: type_elems\n                        .iter()\n                        .zip(expr_elems.iter())\n                        .map(|(type_, expr)| self.infer_expression_type(expr, Some(type_)))\n                        .collect(),\n                    ..type_tuple.clone()\n                })\n            }\n            (syn::Expr::Tuple(syn::ExprTuple { elems, .. }), None) => {\n                syn::Type::Tuple(syn::TypeTuple {\n                    elems: elems\n                        .iter()","sourceCodeStart":90,"sourceCodeEnd":126,"githubUrl":"https://github.com/diesel-rs/diesel/blob/6fa6ed01b24b24248ab2a611698d0a7c6a2e9120/dsl_auto_type/src/auto_type/expression_type_inference.rs#L90-L126","documentation":"auto_type compared a tuple expression with its tuple type hint and found different element counts. The offending input is the tuple expression or the type annotation; one side has more or fewer elements than the other.","triggerScenarios":"Thrown at dsl_auto_type/src/auto_type/expression_type_inference.rs:108 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Make the tuple expression and type hint have the same arity","Remove or correct the tuple type annotation","Split the expression into separately typed parts"],"exampleFix":null,"handlingStrategy":"type-guard","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"6fa6ed01b24b24248ab2a611698d0a7c6a2e9120","analyzedAt":"2026-09-07T01:50:13.074Z","contentChangedAt":"2026-09-07T01:50:13.074Z","schemaVersion":2},"datasetVersion":"2026-09-16T09:17:16.951Z"}