JSON Parser for Prolog
Prolog Gnuplot Ruby
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Latest commit 77dbae4 Aug 26, 2014 Sebastian Lundström Do not indent code blocks


JSON Parser for Prolog

Short Example

$ swipl

?- [load].
% load compiled 0.05 sec, 1,665 clauses

?- json_load_project_modules.
% library(pldoc) compiled into pldoc 0.14 sec, 1,297 clauses
% json(util) compiled into util 0.00 sec, 21 clauses
% json_to_term compiled into json_to_term 0.01 sec, 129 clauses
% term_to_json compiled into term_to_json 0.00 sec, 46 clauses
% json(json) compiled into json 0.01 sec, 192 clauses

?- json:term_json(json([hello-42]), Json).
Json = '{"hello":42}'.

?- json:term_json(Term, '{"hello":42}').
Term = json([hello-42]).


  • Go through escaping once more
  • Add proper error handling


Licensed under the MIT license which can be found in the file LICENSE in the project root.

Coding Guidelines

  • Use empty imports (use_module(mymodule, [])) in order to not pollute the namespace.
  • Always use module prefixes (mymodule:predicate(...)) in order to clarify where things are coming from.
  • Always use the "made-up" module prefix "core:" when calling built-in predicates. This is completely unnecessary, and doesn't even work in all cases, but I think it is a good idea as long as it doesn't cause any problems. This decision may need to be revised when compatibility between different Prologs is investigated.
  • Avoid the if-then-else construct. It just looks ugly.
  • Avoid disjunctions. They are ugly, and can be replaced by properly written helpers. Think: premises are "and", clauses are "or".
  • Use cuts where appropriate, and try to keep each cut on a line by itself unless its placement is obvious and consistent in each clause. PlUnit is excellent at pointing out when tests succeed but leave choice points.
  • Try to avoid spaces within lists and structures, but always use spaces between arguments.
  • Predicates, atoms, etc. should use "this_naming_style" while variables should use "ThisNamingStyle".
  • Try to stick to the PlDoc structure.
  • If in doubt, consult: http://www.ai.uga.edu/mc/plcoding.pdf