@Override
public boolean accept(final ASTVisitor visitor) {
if (!visitAll(visitor, specs)) return false;
for (final Expr ng : preExpr) if (!ng.accept(visitor)) return false;
for (final Var ng : post) if (!visitor.declared(ng)) return false;
return true;
}
@Override
public boolean accept(final ASTVisitor visitor) {
return expr.accept(visitor) && visitor.declared(var);
}