Playground

Interactive engine

Declare a domain, write a Datalog policy, feed runtime facts, and query — running on the real maelys_datalog kernel compiled to WebAssembly.

loading engine

examples

1domainname/arity kind

backend/2 edb
allowed_backend/1 edb
has_text/1 edb
allow/1 idb,query
deny/1 idb,query

2policy.dlDatalog rules

% Allow trusted backends that carry content.
allow(R) :-
    backend(R, B),
    allowed_backend(B),
    has_text(R).

% Deny anything whose backend is not trusted.
deny(R) :-
    backend(R, B),
    not(allowed_backend(B)).

3edb.dlruntime facts

allowed_backend("cli_pivot")
allowed_backend("acp")
backend("req-1", "cli_pivot")
has_text("req-1")
backend("req-2", "unknown_backend")
has_text("req-2")

4queriespred("arg")

allow("req-1")
deny("req-1")
allow("req-2")
deny("req-2")

results

Run solve() to evaluate your queries.

●predicate●variable (Uppercase)●"symbol"●edb · idb · query●% comment·rules end with .·facts of arity 1 or 2