René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"[BUG] Chaining .? (optional select) produces nested Optional(Optional(...))","articleBody":"**Describe the bug**\nChaining multiple .? (optional field select) operations does not work correctly. Each .? in the chain wraps the result in an additional Optional, producing Optional(Optional(Optional(...))) instead of a flat Optional\u003cT\u003e.\n\nFor example:\n\n```cel\na.?b.?c.?d.orValue(\"default\")\n```\n\nfails at runtime, while the equivalent [?] index syntax works fine:\n\n```cel\na[?\"b\"][?\"c\"][?\"d\"].orValue(\"default\")\n```\n\n**cel-go seems to handle this correctly**: The Go reference implementation unwraps an optional operand before applying qualifiers: https://github.com/google/cel-go/blob/master/interpreter/attributes.go#L1298\n\n**To Reproduce**\nCheck which components this affects:\n\n- [ ]  parser\n- [ ]  checker\n- [X]  runtime\n\nSample expression and input that reproduces the issue:\n```cel\na.?b.?c.?d.orValue(\"default\")\n```\n\n**Expected behavior**\nA clear and concise description of what you expected to happen.\n\n`a.?b.?c.?d.orValue(\"default\")` should behave the same way as `a[?\"b\"][?\"c\"][?\"d\"].orValue(\"default\")`, not throw. \n","author":{"url":"https://github.com/LouisCaubet","@type":"Person","name":"LouisCaubet"},"datePublished":"2026-06-11T03:16:31.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/1083/cel-java/issues/1083"}