Removed CLP(Z) from library(json), achieving a 100x speedup in JSON parsing.

src/tests/json/README.md

@@ -0,0 +1,13 @@
+## Benchmarks
+
+### With CLP(Z):
+```
+?- test_json_read.
+   % CPU time: 41.522 seconds
+```
+
+### After removing CLP(Z):
+```
+?- test_json_read.
+   % CPU time: 0.444 seconds
+```

src/tests/json/test_json.pl

@@ -0,0 +1,27 @@
+:- module(test_json, [test_json_read/0]).
+
+:- use_module(library(json)).
+:- use_module(library(lists)).
+:- use_module(library(os)).
+:- use_module(library(pio)).
+:- use_module(library(time)).
+
+test_path(TestName, TestPath) :-
+    getenv("SCRYER_JSON_TESTS_PATH", JsonPath),
+    append(JsonPath, TestName, TestPathChars),
+    atom_chars(TestPath, TestPathChars).
+
+name_parse(Name, Json) :-
+    test_path(Name, Path),
+    once(phrase_from_file(json_chars(Json), Path)).
+
+test_json_read :-
+    name_parse("pass_null.json", _),
+    name_parse("pass_alnum.json", _),
+    name_parse("pass_special.json", _),
+    name_parse("pass_mandatory_escapes.json", _),
+    name_parse("pass_forward_slash.json", _),
+    name_parse("pass_hex.json", _),
+    name_parse("pass_smallfloat.json", _),
+    name_parse("pass_bigfloat.json", _),
+    time(name_parse("pass_everything.json", _)).