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"path": "/t/design-idea-modeling-lifetimes-as-rotational-phases/24140#post_2",
"publishedAt": "2026-04-07T16:36:41.000Z",
"site": "https://internals.rust-lang.org",
"textContent": "To prove this isn't just theoretical, I’ve been looking into how this could be implemented today using procedural macros. A sigma_sync attribute could essentially act as a \"Sigma-island\" within standard Rust, automating the phase transitions for the developer.\n\nThe macro would perform a static analysis of the AST and transform linear code into a series of phase-locked rotations:\n\n\n #[sigma_sync]\n fn process_data() {\n let mut data = 100; // Macro wraps this in SigmaAxis (0°)\n\n // The macro identifies operation points and generates rotations:\n step! { data += 10 }; // Auto-generated: rotate::<120>().execute(...)\n step! { data *= 2 }; // Auto-generated: rotate::<240>().execute(...)\n\n // Cycle completes and returns to 0° automatically\n println!(\"Result: {}\", data);\n }\n\n\nHow it works under the hood:\n\n 1. AST Analysis: The macro counts the operations and divides 360° by the total count to determine the phase offsets.\n 2. Phase Injection: It transforms each `step!` into a `phase.rotate::<N>().execute(...)` chain, ensuring that each phase is consumed and moved to the next.\n 3. Branch Alignment: For `if-else` blocks, the macro can inject \"no-op rotations\" to ensure both branches arrive at the same phase before merging.\n\n\n\nThis approach would allow us to experiment with Sigma-Rotation as a crate (a \"Polonius Emulator\" of sorts) without needing immediate changes to the compiler itself. It provides a safe harbor where memory management is strictly geometric and predictable.\n\nI think this could be a viable path for testing the ergonomics of rotational lifetimes before committing to a full RFC.",
"title": "Design idea: Modeling lifetimes as rotational phases"
}