Expressions

- Simplified ::eval.
- Added standard operand handling.
- Added type information to the value_stack.
This commit is contained in:
Paul Beckingham 2011-06-17 23:53:26 -04:00
parent c77c6f172f
commit c57f880be7

View file

@ -71,89 +71,75 @@ bool Expression::eval (Task& task)
// There are elements in the filter, so the expression must be evaluated
// against each task.
std::vector <Variant> value_stack;
std::vector <std::pair <Variant, std::string> > value_stack;
// TODO Build an on-demand regex cache.
std::vector <std::pair <std::string, std::string> >::iterator arg;
for (arg = _args.begin (); arg != _args.end (); ++arg)
{
if (arg->second == "op")
{
// TODO Need helpers that pop, and error out if necessary.
// Handle the unary operator first.
if (arg->first == "!")
{
if (value_stack.size () < 1)
throw std::string ("Error: Insufficient operands for '!' operator.");
std::string right_type = value_stack.back ().second;
Variant right (value_stack.back ().first);
value_stack.pop_back ();
right = ! right;
value_stack.push_back (std::make_pair (right, ""));
continue; // This only occurs here.
}
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands for '") + arg->first + "' operator.";
// Pop the binary operands first.
std::string right_type = value_stack.back ().second;
Variant right (value_stack.back ().first);
value_stack.pop_back ();
std::string left_type = value_stack.back ().second;
Variant left (value_stack.back ().first);
value_stack.pop_back ();
// Now hte binary operators.
if (arg->first == "and")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left && right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "xor")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = (left && !right) || (!left && right);
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "or")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left || right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "<=")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left <= right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == ">=")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left >= right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "!~")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
// TODO
/*
if left == "description" then it really means description or annotations or project.
@ -163,146 +149,68 @@ bool Expression::eval (Task& task)
else if (arg->first == "!=")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left != right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "=")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
context.debug ("eval left=" + left.format ());
context.debug ("eval right=" + right.format ());
left = left == right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == ">")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left > right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "~")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
// TODO
// TODO We need to compare right against description, all annotations and project.
// TODO Does that mean we need the original lvalue intact, and not a DOM subst?
/*
if left == "description" then it really means description or annotations or project.
if left == "tags" then it just means tags.
*/
}
else if (arg->first == "!")
{
if (value_stack.size () < 1)
throw std::string ("Error: Insufficient operands.");
Variant left (value_stack.back ());
value_stack.pop_back ();
left = ! left;
value_stack.push_back (left);
}
else if (arg->first == "*")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left * right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "/")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left / right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "%")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
// TODO Implement modulus.
}
else if (arg->first == "+")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left + right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "-")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left - right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else if (arg->first == "<")
{
if (value_stack.size () < 2)
throw std::string ("Error: Insufficient operands.");
Variant right (value_stack.back ());
value_stack.pop_back ();
Variant left (value_stack.back ());
value_stack.pop_back ();
left = left < right;
value_stack.push_back (left);
value_stack.push_back (std::make_pair (left, ""));
}
else
@ -313,18 +221,18 @@ bool Expression::eval (Task& task)
else
{
if (arg->second == "lvalue")
value_stack.push_back (Variant (context.dom.get (arg->first, task)));
value_stack.push_back (std::make_pair (Variant (context.dom.get (arg->first, task)), ""));
else if (arg->second == "int")
value_stack.push_back (Variant ((int) strtol (arg->first.c_str (), NULL, 10)));
value_stack.push_back (std::make_pair (Variant ((int) strtol (arg->first.c_str (), NULL, 10)), ""));
else if (arg->second == "number")
value_stack.push_back (Variant (strtod (arg->first.c_str (), NULL)));
value_stack.push_back (std::make_pair (Variant (strtod (arg->first.c_str (), NULL)), ""));
else if (arg->second == "rvalue" ||
arg->second == "string" ||
arg->second == "rx")
value_stack.push_back (Variant (arg->first));
value_stack.push_back (std::make_pair (Variant (unquoteText (arg->first)), ""));
else
throw std::string ("Error: Expression::eval unrecognized operand '") + + "'.";
@ -332,7 +240,7 @@ bool Expression::eval (Task& task)
}
// Coerce stack element to boolean.
Variant result (value_stack.back ());
Variant result (value_stack.back ().first);
//context.debug ("eval result=" + result.format ());
value_stack.pop_back ();
bool pass_fail = result.boolean ();