writing-hashql-jexpr

J-Expr syntax in HashQL uses string paths, arrays for function calls, and objects with # keys to compose queries. Paths support namespacing and labeled arguments, while data constructors like #literal, #struct, #list, #tuple, and #dict enable entity filtering and data definition across namespaced paths.

HashQL data constructors (#literal, #struct, #tuple, #list, #dict, #type) define structured data within J-Expr queries. They enable strict JSON-based representation with labeled arguments, supporting entity creation, filtering, and type embedding via the #type DSL for function calls and parser references.

Yes, J-Expr supports control and type constructs including let bindings, fn function definitions, if conditionals, type declarations, newtype definitions, and use statements. These compose with paths and data constructors to build complex entity queries and transformations.

J-Expr path syntax handles namespacing through object structures with # keys and supports labeled arguments via objects passed to function calls. This enables precise data filtering and entity selection across hierarchical data structures with explicit type and value specification.

In J-Expr, arrays represent function calls with positional arguments, while objects with # keys define data constructors and labeled argument structures. This dual representation enables both functional composition and structured data definition within a single JSON-based query format.