{"record":{"id":"59cb304a7f2f81e9","repo":"leptos-rs/leptos","slug":"element-needs-to-have-a-name","errorCode":null,"errorMessage":"element needs to have a name","messagePattern":"element needs to have a name","errorType":"panic","errorClass":null,"httpStatus":null,"severity":"error","filePath":"leptos_macro/src/view/mod.rs","lineNumber":1911,"sourceCode":"}\n\nfn convert_to_snake_case(name: String) -> String {\n    if !is_case(&name, Snake) {\n        name.to_case(Snake)\n    } else {\n        name\n    }\n}\n\npub(crate) fn ident_from_tag_name(tag_name: &NodeName) -> Ident {\n    match tag_name {\n        NodeName::Path(path) => path\n            .path\n            .segments\n            .iter()\n            .next_back()\n            .map(|segment| segment.ident.clone())\n            .expect(\"element needs to have a name\"),\n        NodeName::Block(_) => {\n            let span = tag_name.span();\n            proc_macro_error2::emit_error!(\n                span,\n                \"blocks not allowed in tag-name position\"\n            );\n            Ident::new(\"\", span)\n        }\n        _ => Ident::new(\n            &tag_name.to_string().replace(['-', ':'], \"_\"),\n            tag_name.span(),\n        ),\n    }\n}\n\npub(crate) fn full_path_from_tag_name(tag_name: &NodeName) -> Option<ExprPath> {\n    match tag_name {\n        NodeName::Path(path) => Some(path.clone()),","sourceCodeStart":1893,"sourceCodeEnd":1929,"githubUrl":"https://github.com/leptos-rs/leptos/blob/32d20f6c9d517451d77beb68d88c7716823dac41/leptos_macro/src/view/mod.rs#L1893-L1929","documentation":"ident_from_tag_name in leptos_macro's view! macro derives the element identifier from the tag's AST path. It unwraps the last path segment; if the path has zero segments (an empty path in the tag-name position), the expect panics with 'element needs to have a name'. This is a compile-time macro panic, so it aborts the rustc build rather than failing at runtime.","triggerScenarios":"Using view! with a tag name that parses to an empty syn::Path (e.g. an empty or malformed tag-name token stream), so path.segments.iter().next_back() returns None.","commonSituations":"Hand-written or code-generated macro invocations where a variable or bad token stream is spliced into the tag-name position; broken custom derive/proc-macro tooling emitting empty paths; copy-paste corruption in view! markup.","solutions":["Inspect the view! call reported by rustc and give the element a concrete tag name (e.g. <div>...</div>).","If the tag name comes from a macro-generated token stream, check the generator for empty paths being emitted.","If you intended a dynamic element, use a valid block/tag expression instead of an empty path in tag position."],"exampleFix":"// before\nview! { <>{children}</> with an empty tag path }\n// after\nview! { <div>{children}</div> }","handlingStrategy":"validation","validationCode":"fn has_tag_name(tag: &NodeName) -> bool {\n    match tag {\n        NodeName::Path(p) => !p.path.segments.is_empty(),\n        _ => true,\n    }\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Use concrete tag names in view!; validate generators emitting tag tokens"],"tags":["leptos","proc-macro","compile-time","view-macro"],"backgroundTag":"macro-panic-empty-tag-name","analyzedSha":"32d20f6c9d517451d77beb68d88c7716823dac41","analyzedAt":"2026-09-01T18:55:42.580Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-09T01:17:15.007Z"}