{"record":{"id":"4c454ba7b0a2f4d8","repo":"emberjs/ember.js","slug":"cannot-use-mustaches-in-an-elements-tagname","errorCode":null,"errorMessage":"Cannot use mustaches in an elements tagname","messagePattern":"Cannot use mustaches in an elements tagname","errorType":"validation","errorClass":"SyntaxError","httpStatus":null,"severity":"error","filePath":"packages/@glimmer/syntax/lib/parser/handlebars-node-visitors.ts","lineNumber":263,"sourceCode":"        strip,\n      });\n    } else {\n      const { path, params, hash } = acceptCallNodes(this, rawMustache);\n      mustache = b.mustache({\n        path,\n        params,\n        hash,\n        trusting: !escaped,\n        loc: this.source.spanFor(loc),\n        strip,\n      });\n    }\n\n    switch (tokenizer.state) {\n      // Tag helpers\n      case 'tagOpen':\n      case 'tagName':\n        throw generateSyntaxError(`Cannot use mustaches in an elements tagname`, mustache.loc);\n\n      case 'beforeAttributeName':\n        addElementModifier(this.currentStartTag, mustache);\n        break;\n      case 'attributeName':\n      case 'afterAttributeName':\n        this.beginAttributeValue(false);\n        this.finishAttributeValue();\n        addElementModifier(this.currentStartTag, mustache);\n        tokenizer.transitionTo(BEFORE_ATTRIBUTE_NAME);\n        break;\n      case 'afterAttributeValueQuoted':\n        addElementModifier(this.currentStartTag, mustache);\n        tokenizer.transitionTo(BEFORE_ATTRIBUTE_NAME);\n        break;\n\n      // Attribute values\n      case 'beforeAttributeValue':","sourceCodeStart":245,"sourceCodeEnd":281,"githubUrl":"https://github.com/emberjs/ember.js/blob/26f97246a8bf2e28edf26ac3093da2e86c04ffc5/packages/@glimmer/syntax/lib/parser/handlebars-node-visitors.ts#L245-L281","documentation":"Error \"Cannot use mustaches in an elements tagname\" thrown in emberjs/ember.js.","triggerScenarios":"Thrown at packages/@glimmer/syntax/lib/parser/handlebars-node-visitors.ts:263 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":"26f97246a8bf2e28edf26ac3093da2e86c04ffc5","analyzedAt":"2026-09-01T05:01:28.182Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}