Merge branch 'master' of https://github.com/duboissim/LINFO2335_M1

solution.pl

@@ -62,13 +62,22 @@ cols(Table, Cols) :-
 Unifies Row, one result at a time, with each row in the given Table.
 If the given table does not exist, the predicate should fail.
 */
+row(Table, _) :-
+	\+ tabl(Table, _),
+	throw("Table doesn't exist"),
+	!. 
+
+row(Table, _) :-
+	tabl(Table, Cols),
+	length(Cols, L),
+	\+ current_predicate(Table/L),
+	!.
+
 row(Table, Row) :-
-    tabl(Table, Cols) ->
-    (
-		length(Cols, L),
-		length(Row, L),
-    	apply(Table, Row) 
-    ); throw("Table doesn't exist").
+    tabl(Table, Cols), 
+	length(Cols, L),
+	length(Row, L),
+	apply(Table, Row).
 
 :- dynamic rows/1.
 /*
@@ -81,6 +90,12 @@ rows(Table) :-
     throw(table_does_not_exist(Table)),
     !.
 
+rows(Table) :-
+	tabl(Table, Cols),
+	length(Cols, L),
+	\+ current_predicate(Table/L),
+	!.
+
 rows(Table) :-
     row(Table, Row),
     writeln(Row),
@@ -218,6 +233,17 @@ For example:
 findall(Values, selec(persons,[+id,+first],[],Values), Projections)
 returns: Projections = [[0, "Jeffrey"], [1, "Lorena"], [2, "Joseph"], ...
 */
+selec(Table, _, _, _) :-
+	\+ tabl(Table, _),
+	throw("Table doesn't exist"),
+	!.
+
+selec(Table, _, _, _) :-
+	tabl(Table, Cols),
+	length(Cols, L),
+	\+ current_predicate(Table/L),
+	!.
+
 selec(Table, Selector, Cond, Projection) :-
 	tabl(Table, Cols),
 	row(Table, R),
@@ -231,8 +257,6 @@ selec(Table, *, Cond, Projection) :-
 	does_match(Cond, Table, R),
 	Projection = Cols/R.
 
-%base case
-selector(_,_,[],ColumnNames, ColumnValue, ColumnNames, ColumnValue):-!.
 /**
  * Row: A row from the table
  * Cols: name of the column of the table
@@ -242,6 +266,9 @@ selector(_,_,[],ColumnNames, ColumnValue, ColumnNames, ColumnValue):-!.
  * ColumnNames: List returning the column(s) name(s)
  * ColumnValue: List returning the row values for each column 
 */
+
+selector(_,_,[],ColumnNames, ColumnValue, ColumnNames, ColumnValue):-!.
+
 selector(Row, Cols, [+Selector|Selectors], AccCols, AccVals, ColumnNames, ColumnValue):-
 	(member(Selector, Cols) ->
 		%find the value corresponding to the column in the row