Add some ad-hoc test code to prolog/util.py

1 files changed, 12 insertions, 0 deletions

diff --git a/prolog/util.py b/prolog/util.py
index 438c068..85589b5 100644
--- a/prolog/util.py
+++ b/prolog/util.py
@@ -143,3 +143,15 @@ def map_vars(before, after, line, rule):
         mapping_all = {k: v for k, v in mapping.items()}
         mapping_all.update(more_mapping)
         yield mapping_all
+
+# Basic sanity check.
+if __name__ == '__main__':
+    rule = tokenize('dup([H|T], [H1|T1]) :- dup(T1, T2). ')
+    line = tokenize('dup([H|T], [H1|T1]) :-')
+    before = tokenize("dup([A0|A1], [A2|A3])")
+    after = tokenize("dup([A0|A1], [A5, A4|A3])")
+    var_names = rename_vars(before)
+    rename_vars(after, var_names)
+
+    for mapping in map_vars(before, after, line, rule):
+        print(mapping)