datalog-parser

A Datalog parser. This parser is used by Datahike and follows the Datalog dialect of Datomic.

Usage

Add the current release of io.lambdaforge/datalog-parser to your project.clj. Start a repl and run:

(require '[datalog.parser :as parser])

(parser/parse '[:find ?x :in $ ?y :where [?x :z ?y]])

;;=> (namespaces omitted for brevity)
;; #Query{:qfind  #FindRel{:elements [#Variable{:symbol ?x}]}
;;        :qwith  nil
;;        :qin    [#BindScalar{:variable #SrcVar{:symbol $}}
;;                 #BindScalar{:variable #Variable{:symbol ?y}}]
;;        :qwhere [#Pattern{:source #DefaultSrc{}
;;                          :pattern [#Variable{:symbol ?x}
;;                                    #Constant{:value  :z}
;;                                    #Variable{:symbol ?y}]}]}

For more examples look at the tests.

Benchmarking and Profiling

To benchmark or profile the parser, change to the parser-perf namespace or require it:

(in-ns 'datalog.parser-perf')

Then run the parse benchmark or profiler:

(parse)
(profile)

To see the produced flame graph, you can start a web server at port:

(in-ns 'datalog.parser-perf')
(prof/server-files port)

TODO

0.2.0

Unparsing support, missing types:

• PullSpec
• PullAttrName
• PullReverseAttrName
• PullLimitExpr
• PullDefaultExpr
• PullWildcard
• PullRecursionLimit
• PullMapSpecEntry
• PullAttrWithOpts

License

Copyright © 2020 lambdaforge UG (haftungsbeschränkt), Nikita Prokopov

This program and the accompanying materials are made available under the terms of the Eclipse Public License 1.0.