Why Clojure Autogensyms Fail Inside Functions and How to Fix It

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A developer building SPARQL queries in Clojure using the Flint library encountered a subtle bug when trying to generate unique symbols for reusable query fragments. The problem arose because autogensyms — symbols with a trailing # inside a syntax quote — are resolved at read time, not at runtime, causing the same symbol to be reused across multiple function calls. This behavior is by design for macros, where autogensym scope is limited to a single macro expansion, but it breaks down when used inside regular functions. As a result, query variables intended to be distinct across calls ended up sharing the same generated symbol, producing incorrect query bindings. The article explores this quoting limitation in Clojure and points toward alternative approaches for generating truly unique symbols at runtime.

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