SystemCallFragment.cpp

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#ifndef _MADARA_NO_KARL_
 
#include "madara/expression/LeafNode.h"
#include "madara/expression/SystemCallFragment.h"
#include "madara/expression/Visitor.h"
 
madara::expression::SystemCallFragment::SystemCallFragment(
    madara::knowledge::ThreadSafeContext& context, const ComponentNodes& nodes)
  : SystemCallNode(context, nodes)
{
}
 
// Dtor
madara::expression::SystemCallFragment::~SystemCallFragment(void) {}
 
madara::knowledge::KnowledgeRecord madara::expression::SystemCallFragment::item(
    void) const
{
  return madara::knowledge::KnowledgeRecord(nodes_.size());
}
 
madara::knowledge::KnowledgeRecord
madara::expression::SystemCallFragment::prune(bool& can_change)
{
  // user can always change a function, and we have no control over
  // what it does. Consequently, a function node cannot be pruned out
  // under any situation
  can_change = true;
 
  madara::knowledge::KnowledgeRecord result;
 
  for (ComponentNodes::iterator i = nodes_.begin(); i != nodes_.end(); ++i)
  {
    bool arg_can_change = false;
    result = (*i)->prune(arg_can_change);
 
    if (!arg_can_change && dynamic_cast<LeafNode*>(*i) == 0)
    {
      delete *i;
      *i = new LeafNode(*(this->logger_), result);
    }
  }
 
  if (nodes_.size() != 3)
  {
    madara_logger_ptr_log(logger_, logger::LOG_ERROR,
        "madara::expression::SystemCallFragment: "
        "KARL COMPILE ERROR:"
        "System call fragment"
        " requires three arguments, e.g."
        " #fragment ('hello world', 0, 4) will return 'hello'\n");
 
    throw exceptions::KarlException(
        "madara::expression::SystemCallFragment: "
        "KARL COMPILE ERROR: "
        "System call fragment"
        " requires three arguments, e.g."
        " #fragment ('hello world', 0, 4) will return 'hello'\n");
  }
 
  return result;
}
 
madara::knowledge::KnowledgeRecord
madara::expression::SystemCallFragment::evaluate(
    const madara::knowledge::KnowledgeUpdateSettings& settings)
{
  knowledge::KnowledgeRecord return_value;
 
  if (nodes_.size() == 3)
  {
    // grab the first and last ranges
    unsigned int first =
        (unsigned int)nodes_[1]->evaluate(settings).to_integer();
    unsigned int last =
        (unsigned int)nodes_[2]->evaluate(settings).to_integer();
 
    madara_logger_ptr_log(logger_, logger::LOG_MINOR,
        "madara::expression::SystemCallFragment: "
        "System call fragment is returning segment [%d-%d].\n",
        first, last);
 
    return nodes_[0]->evaluate(settings).fragment(first, last);
  }
 
  else
  {
    madara_logger_ptr_log(logger_, logger::LOG_ERROR,
        "madara::expression::SystemCallFragment: "
        "KARL RUNTIME ERROR:"
        "System call fragment"
        " requires three arguments, e.g."
        " #fragment ('hello world', 0, 4) will return 'hello'\n");
 
    throw exceptions::KarlException(
        "madara::expression::SystemCallFragment: "
        "KARL RUNTIME ERROR: "
        "System call fragment"
        " requires three arguments, e.g."
        " #fragment ('hello world', 0, 4) will return 'hello'\n");
  }
 
  return return_value;
}
 
// accept a visitor
void madara::expression::SystemCallFragment::accept(
    madara::expression::Visitor& visitor) const
{
  visitor.visit(*this);
}
 
#endif  // _MADARA_NO_KARL_