Building Graph Query DSLs in Clojure: Handling Variables with Symbols and Macros

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A Clojure developer has published a follow-up post exploring how to build domain-specific languages (DSLs) for graph database queries in Clojure, focusing on Datomic and SPARQL. The article explains why SQL-oriented tools like HoneySQL differ from graph query languages, which rely on pattern-matching variables such as ?person or ?friend to bind matched nodes. A core challenge discussed is that Clojure symbols — the natural choice for query variables — must be quoted to prevent the runtime from evaluating them as value references. The post also examines Flint, a library that expresses SPARQL queries using Datomic-style Clojure data structures, and highlights the risk of variable name collisions when queries are built programmatically. The author adopts a personal, exploratory writing style to document the learning process, contrasting it with formal tutorial formats.

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