private List listChildren(Expr expr) {
			final List children = new ArrayList();

			if (expr instanceof StoreExpr) {
				expr = ((StoreExpr) expr).target();
			}

			expr.visitChildren(new TreeVisitor() {
				public void visitStoreExpr(final StoreExpr expr) {
					// Ignore the RHS.
					children.add(expr.target());
				}

				public void visitExpr(final Expr expr) {
					children.add(expr);
				}
			});

			return children;
		}