constraints come from the interpreter, not from the syntax

> in my book just specifying a data-structure doesn't make a language

correct, it does not

what makes it a language is defining constraints on that structure and rules for how it's interpreted

that works both for clojure (where the data structure can involve lists, vectors, maps and primitives) and traditional lisps (where data structure is lists, or to be precise cons cells and primitives)

in both cases macros can be used and are used (but don't have to be used) to prevent immediate evaluation of those data structures according to host language rules and instead change how they are evaluated according to DSL author's rules

for example, datomic queries are just data structures, but they clearly form a constrained language with well defined semantics and the fact that they're not implemented via macros doesn't make them less of a DSL