JanWielemaker / refactor

Refactoring Tools for SWI-Prolog

refactor

Refactoring Tools for SWI-Prolog

Installation

To install the refactoring tools, just follow the next sequence of commands in your SWI-Prolog shell:

  $ swipl
  
  ?- pack_install('https://github.com/edisonm/refactor.git').
  true.

Usage

Although this library lacks documentation, due its alfa status and still changing, there are some tests in tests/ where you can see useful examples about its usage. Some examples follows:

?- [library(refactor)].
true.

?- cd(tests).
true.

?- replace_term(a(B), aa(B), [file(repl_conj)]).
% 3 changes of 3 attempts
% Saved changes in index 1
true.

To review the changes, use rshow:

?- rshow.
diff -ruN repl_conj.pl -
--- repl_conj.pl (source)
+++ repl_conj.pl (target)
@@ -1,15 +1,15 @@
 :- module(repl_conj, [repl_conj/0]).
 
 repl_conj :-
-    a(C),
+    aa(C),
     b(b),
     c(C),
     d(d).
 repl_conj :-
-    a(a),
+    aa(a),
     b(b).
 
-a(_).
+aa(_).
 b(_).
 c(_).
 d(_).
true.

To undo the changes, use rreset, and to accept them use rcommit. Continuous calls to refactor predicates can be stacked so you could implement complex scenarios via small ones. Some refactoring scenarios that results of the composition of multiple changes are implemented in the library ref_scenarios.pl.

Other complex scenarios are implemented in its own modules, as follows:

• deref_reexport.pl helps to replace reexport declarations by use_module declarations

• file_to_module.pl convert included files to modules

• move_preds.pl helps to move predicates from one file to another

Papers

Edison Mera, Jan Wielemaker: Porting and refactoring Prolog programs: the PROSYN case study. TPLP 13(4-5-Online-Supplement) (2013) http://journals.cambridge.org/downloadsup.php?file=/tlp2013003.pdf