{"record":{"id":"1fcf718cbb74f142","repo":"gleam-lang/gleam","slug":"decision-tree-with-no-subjects","errorCode":null,"errorMessage":"decision tree with no subjects","messagePattern":"decision tree with no subjects","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"compiler-core/src/javascript/decision.rs","lineNumber":1324,"sourceCode":"        }\n\n        assignments\n    }\n\n    /// Give a unique name to the subject of a let expression (if it needs one\n    /// and it's not already a variable) and keep track of that name in case it\n    /// needs to be referenced later.\n    ///\n    fn assign_let_subject(\n        &mut self,\n        arena: &'doc DocumentArena<'a, 'doc>,\n        compiled_case: &'a CompiledCase,\n        subject: &'a TypedExpr,\n    ) -> SubjectAssignment<'a, 'doc> {\n        let variable = compiled_case\n            .subject_variables\n            .first()\n            .expect(\"decision tree with no subjects\");\n        let assignment = assign_subject(arena, self.expression_generator, subject, Ordering::Loose);\n        self.set_value(variable, assignment.name());\n        self.bind(assignment.name(), variable);\n        assignment\n    }\n\n    fn local_var(&mut self, name: &EcoString) -> EcoString {\n        self.expression_generator.local_var(name)\n    }\n\n    fn next_local_var(&mut self, name: &EcoString) -> EcoString {\n        self.expression_generator.next_local_var(name)\n    }\n\n    /// Records that a given pattern `variable` has been assigned a runtime\n    /// `value`. For example if we had something like this:\n    ///\n    /// ```txt","sourceCodeStart":1306,"sourceCodeEnd":1342,"githubUrl":"https://github.com/gleam-lang/gleam/blob/7e623aa83da3776faee50ca4ab9a6c40124acd95/compiler-core/src/javascript/decision.rs#L1306-L1342","documentation":"Error \"decision tree with no subjects\" thrown in gleam-lang/gleam.","triggerScenarios":"Thrown at compiler-core/src/javascript/decision.rs:1324 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"7e623aa83da3776faee50ca4ab9a6c40124acd95","analyzedAt":"2026-08-17T00:07:02.091Z","schemaVersion":2},"datasetVersion":"2026-08-17T04:17:16.089Z"}