package org.rascalmpl.interpreter.cursors;
import org.eclipse.imp.pdb.facts.IInteger;
import org.eclipse.imp.pdb.facts.IList;
import org.eclipse.imp.pdb.facts.ITuple;
import org.eclipse.imp.pdb.facts.IValue;
import org.eclipse.imp.pdb.facts.IValueFactory;
import org.rascalmpl.library.util.Cursor;
public class TupleSelectContext extends Context {
private final Context ctx;
private final int fields[];
private final ITuple tuple;
public TupleSelectContext(Context ctx, int fields[], ITuple tuple) {
this.ctx = ctx;
this.fields = fields;
this.tuple = tuple;
}
@Override
public IValue up(IValue focus) {
ITuple sub = (ITuple)focus;
int i = 0;
ITuple newTuple = tuple;
for (IValue elt: sub) {
newTuple = newTuple.set(fields[i], elt);
i++;
}
return new TupleCursor(newTuple, ctx);
}
@Override
public IList toPath(IValueFactory vf) {
IInteger[] labels = new IInteger[fields.length];
for (int i = 0; i < fields.length; i++) {
labels[i] = vf.integer(fields[i]);
}
return ctx.toPath(vf).append(vf.constructor(Cursor.Nav_selectByIndex, vf.list(labels)));
}
}