{"record":{"id":"5fdb59232232b715","repo":"BoundaryML/baml","slug":"internal-error-occurred-while-resolving-repr-of-field","errorCode":null,"errorMessage":"Internal error occurred while resolving repr of field {:?}","messagePattern":"Internal error occurred while resolving repr of field (.+?)","errorType":"exception","errorClass":"anyhow::Error","httpStatus":null,"severity":"error","filePath":"engine/baml-lib/baml-core/src/ir/repr.rs","lineNumber":2158,"sourceCode":"    pub docstring: Option<Docstring>,\n}\n\nimpl WithRepr<Field> for FieldWalker<'_> {\n    fn attributes(&self, db: &ParserDatabase) -> NodeAttributes {\n        let (meta, constraints) = to_ir_attributes(db, self.get_default_attributes());\n        let attributes = NodeAttributes {\n            meta,\n            constraints,\n            span: Some(self.span().clone()),\n            identifier_span: Some(self.ast_field().identifier().span().clone()),\n            symbol_spans: HashMap::new(),\n        };\n\n        attributes\n    }\n\n    fn repr(&self, db: &ParserDatabase) -> Result<Field> {\n        let ast_field_type = self.ast_field().expr.as_ref().ok_or(anyhow!(\n            \"Internal error occurred while resolving repr of field {:?}\",\n            self.name(),\n        ))?;\n        let field_type_attributes = WithRepr::attributes(ast_field_type, db);\n        let field_type = ast_field_type.repr(db)?;\n        Ok(Field {\n            name: self.name().to_string(),\n            r#type: Node {\n                elem: field_type,\n                attributes: field_type_attributes,\n            },\n            docstring: self.get_documentation().map(Docstring),\n        })\n    }\n}\n\ntype ClassId = String;\n","sourceCodeStart":2140,"sourceCodeEnd":2176,"githubUrl":"https://github.com/BoundaryML/baml/blob/bd85ce9dee1463ff04d27efd20531013a4ff46c1/engine/baml-lib/baml-core/src/ir/repr.rs#L2140-L2176","documentation":"When converting an AST field into an IR Field, BAML expects the field's type expression (ast_field().expr) to be present. If it is None — meaning the parser produced a field node without a type expression — BAML raises this internal error since repr cannot proceed. It is an invariant violation rather than a user-facing schema mistake.","triggerScenarios":"Field::repr(db) called on a field whose AST node has no expression for its type — typically the result of a parser bug, a partially-parsed construct, or a schema syntax the parser mishandled.","commonSituations":"Corrupted or truncated .baml file; exotic/unusual field syntax that slips past the grammar; BAML compiler version bug; empty or malformed field declaration that wasn't caught as a parse error.","solutions":["Inspect the field named in the error and rewrite its declaration in standard syntax.","Check for truncated or merge-conflicted lines in the .baml file.","Upgrade BAML to the latest version — this may be a fixed parser bug.","If the file looks valid, file an issue with BAML including the field definition."],"exampleFix":"// before (truncated/corrupt)\nclass User {\n  name\n}\n// after\nclass User {\n  name string\n}","handlingStrategy":"try-catch","validationCode":"# basic sanity: every class field line has a type token\nimport re\nfor line in src.splitlines():\n    m = re.match(r'^\\s*(\\w+)\\s*$', line)\n    if m and not line.strip().startswith('//'):\n        print(f\"field without type: {line.strip()}\")","typeGuard":null,"tryCatchPattern":"match field.repr(db) {\n    Ok(f) => f,\n    Err(e) if e.to_string().contains(\"Internal error occurred while resolving repr of field\") => {\n        eprintln!(\"likely parser bug; rewrite field or upgrade baml: {e:#}\");\n        return Err(e);\n    }\n    Err(e) => return Err(e),\n}","preventionTips":["Keep .baml files free of merge-conflict artifacts and truncation.","Write field declarations in standard `name Type` syntax.","Upgrade BAML and report reproducible internal errors upstream."],"tags":["baml","internal","parser","invariant"],"backgroundTag":"internal-invariant-violation","analyzedSha":"bd85ce9dee1463ff04d27efd20531013a4ff46c1","analyzedAt":"2026-09-12T03:38:25.718Z","contentChangedAt":"2026-09-12T03:38:25.718Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}