Data commit

Task/String-prepend/Prolog/string-prepend-1.pro

@@ -0,0 +1,12 @@
+:- op(200, xfx, user:(=+)).
+
+%% +Prepend =+ +Chars
+%
+%    Will destructively update Chars
+%    So that Chars = Prepend prefixed to Chars.
+%    eazar001 in ##prolog helped refine this approach.
+
+[X|Xs] =+ Chars :-
+  append(Xs, Chars, Rest),
+  nb_setarg(2, Chars, Rest),
+  nb_setarg(1, Chars, X).

Task/String-prepend/Prolog/string-prepend-2.pro

@@ -0,0 +1,2 @@
+?- Str = `World!`, `Hello, ` =+ Str.
+Str = "Hello, World!".