From c530682030e80ee2de2c263471e5eda7a3392e84 Mon Sep 17 00:00:00 2001 From: Marcos Magueta Date: Sat, 11 Jul 2026 03:07:56 -0300 Subject: working vm: parser, admission with totality checks, solver and repl --- lib/world.mli | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 lib/world.mli (limited to 'lib/world.mli') diff --git a/lib/world.mli b/lib/world.mli new file mode 100644 index 0000000..76ad316 --- /dev/null +++ b/lib/world.mli @@ -0,0 +1,67 @@ +(** Worlds: the store of relations, and the loader that builds the + standalone one. + + Decision 4 of the integration document: the VM is parameterized + over a world. This module gives the module type every host + satisfies, the standalone in-memory world, and the loader that + admits a parsed program into it. Admission is where totality is + enforced: a program that gets a world is a program whose queries + terminate. *) + +(** A compiled relational expression: what rule bodies and queries + are made of after names are resolved. *) +type expr = + | Apply of string * Pattern.t Label.Map.t + | And of expr * expr + | Or of expr * expr + +type rule = { + rule_name : string; + head : Pattern.t Label.Map.t; + body : expr; + witness : Label.t option; + (** For a recursive rule, the label whose argument strictly + decreases. The VM requires it ground before unfolding, + which is what turns the admission proof into runtime + termination. [None] on non-recursive rules. *) +} + +(** The builtin domains a schema may constrain an attribute by. *) +type domain = D_integer | D_natural | D_rational | D_string + +(** How a relation is defined. *) +type def = + | Table of { schema : (Label.t * domain) list; facts : Term.t Label.Map.t list } + (** Extensional: a schema and finite stored tuples. *) + | Rules of rule list (** Intensional: defined by admitted rules. *) + +(** What a host must answer for the VM to run: which relation lives + under a name. Builtins are the VM's own and are not consulted + here. *) +module type WORLD = sig + type t + + val find : t -> string -> def option +end + +type error + +val pp_error : Format.formatter -> error -> unit + +(** The standalone world: an immutable catalog loaded from program + text. This is Sol as a separate language; there are no branches, + no transitions, only the pure fragment. *) +module Standalone : sig + type t + + val find : t -> string -> def option + + val load : Ast.statement list -> (t * expr list, error) result + (** Admits a program: registers relations, checks every fact + against its schema and domains, compiles rules and queries, + and enforces totality. Rejected, not deferred: a recursive + rule without a structural decrease witness, a mutual + recursion cycle, an unknown relation, or an ill-typed fact is + an [error], and no world exists. Returns the world and the + query expressions in program order. *) +end -- cgit v1.2.3