rotn Class Reference

#include <rpnfunc.h>

Inheritance diagram for rotn:

Collaboration diagram for rotn:

List of all members.

Public Member Functions
	rotn ()
	rotn (deque< rpnbase * > &ds, bool const evaluate=true)
	~rotn ()
rpnbase *	copy () const
void	visit (deque< rpnbase * > &ds, rpninteger &n)
string const	name () const
void	eval (deque< rpnbase * > &ds)

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Detailed Description

Definition at line 230 of file rpnfunc.h.

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Constructor & Destructor Documentation

rotn::rotn

(

)

[inline]

Definition at line 234 of file rpnfunc.h.

Referenced by copy().

{}

rotn::rotn	(	deque< rpnbase * > &	ds,
		bool const	evaluate = true
	)

Definition at line 499 of file rpnfunc.cpp.

References eval().

{
  if (evaluate)
    eval(ds);
  else
    ds.push_front(this);
}

rotn::~rotn

(

)

[inline]

Definition at line 236 of file rpnfunc.h.

{}

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Member Function Documentation

rpnbase * rotn::copy

(

)

const [virtual]

Reimplemented from rpnfunction.

Definition at line 507 of file rpnfunc.cpp.

References rotn().

{
  return new rotn();
}

void rotn::eval

(

deque< rpnbase * > &

ds

)

[virtual]

Reimplemented from rpnfunction.

Definition at line 512 of file rpnfunc.cpp.

References rpnbase::accept(), and rpnbase::dec().

Referenced by rotn().

{
  if (!ds.empty())
    ds[0]->accept(ds,*this);

  dec();
}

string const rotn::name

(

)

const [inline, virtual]

Reimplemented from rpnfunction.

Definition at line 241 of file rpnfunc.h.

{ return string("rotn"); }

void rotn::visit	(	deque< rpnbase * > &	ds,
		rpninteger &	n
	)			[virtual]

Reimplemented from rpnfunction.

Definition at line 520 of file rpnfunc.cpp.

References rpnbase::dec(), rpnbase::isinteger(), and rpninteger::num.

{
  if (k.num==0) //no rotation
    return;

  rpnbase* x0 = ds.front();
  ds.pop_front();
  rpnbase* x1 = ds.front();
  ds.pop_front();

  if (x1->isinteger())
  {
    int n = ((rpninteger*)x1)->num;

    // Valid state to rotate data. 
    if ((n>0)&&(ds.size()>=(unsigned int)n))
    {
//       STL defines rotation in a minimalistic sense - a positive
//       integer mapping an element maps it back to the start.
//       While this is mathematical, for operational use a +ve and
//       -ve direction is easier. +k rotates it k times, -k is in 
//       the other direction.   

      unsigned int k2 = (n-k.num)%n;
      rotate(ds.begin(),ds.begin()+k2,ds.begin()+n);

      x0->dec();
      x1->dec();

      return;
        
    }
  }

  // Error: restore the stack. 
  ds.push_front(x1);
  ds.push_front(x0);
}

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The documentation for this class was generated from the following files:

• rpn/rpnfunc.h
• rpn/rpnfunc.cpp