source: git/factory/cf_iter.cc @ 72dd6e

/* emacs edit mode for this file is -*- C++ -*- */
/* $Id: cf_iter.cc,v 1.2 1997-06-19 12:24:23 schmidt Exp $ */

#include <config.h>

#include "assert.h"

#include "cf_defs.h"
#include "cf_iter.h"
#include "int_cf.h"
#include "int_poly.h"


CFIterator::CFIterator()
{
    data = 0; cursor = 0;
    ispoly = false; hasterms = false;
}

CFIterator::CFIterator( const CFIterator & i )
{
    data = i.data;
    cursor = i.cursor;
    ispoly = i.ispoly;
    hasterms = i.hasterms;
}

CFIterator::CFIterator( const CanonicalForm & f )
{
    if ( f.inBaseDomain() || f.inQuotDomain() ) {
        data = f; cursor = 0;
        ispoly = false; hasterms = true;
    }
    else {
        data = f;
        cursor = ((InternalPoly*)(f.value))->firstTerm;
        ispoly = true; hasterms = true;
    }
}

CFIterator::CFIterator( const CanonicalForm & f, const Variable & v )
{
    ASSERT( !f.inQuotDomain(), "illegal iterator" );
    ASSERT( v.level() > 0, "illegal iterator" );
    if ( f.inBaseDomain() ) {
        data = f; cursor = 0;
        ispoly = false; hasterms = true;
    }
    else {
        if ( f.mvar() == v ) {
            data = f;
            cursor = ((InternalPoly*)(f.value))->firstTerm;
            ispoly = true; hasterms = true;
        }
        else  if ( v > f.mvar() ) {
            data = f; cursor = 0;
            ispoly = false; hasterms = true;
        }
        else {
            data = swapvar( f, v, f.mvar().next() );
            if ( data.mvar() == f.mvar().next() ) {
                cursor = ((InternalPoly*)(data.value))->firstTerm;
                ispoly = true; hasterms = true;
            }
            else {
                cursor = 0;
                ispoly = false; hasterms = true;
            }
        }
    }
}

CFIterator::~CFIterator()
{
    data = 0; cursor = 0;
}

CFIterator&
CFIterator::operator= ( const CFIterator & i )
{
    if ( this != &i ) {
        data = i.data;
        cursor = i.cursor;
        ispoly = i.ispoly;
        hasterms = i.hasterms;
    }
    return *this;
}

CFIterator&
CFIterator::operator= ( const CanonicalForm & f )
{
    if ( f.inBaseDomain() || f.inQuotDomain() ) {
        data = f; cursor = 0;
        ispoly = false; hasterms = true;
    }
    else {
        data = f;
        cursor = ((InternalPoly*)(f.value))->firstTerm;
        ispoly = true; hasterms = true;
    }
    return *this;
}

CFIterator&
CFIterator::operator++ ()
{
    ASSERT( hasterms, "illegal term" );
    if ( ispoly ) {
        cursor = cursor->next;
        hasterms = cursor != 0;
    }
    else
        hasterms = false;
    return *this;
}

CFIterator&
CFIterator::operator++ ( int )
{
    ASSERT( hasterms, "illegal term" );
    if ( ispoly ) {
        cursor = cursor->next;
        hasterms = cursor != 0;
    }
    else
        hasterms = false;
    return *this;
}

int
CFIterator::hasTerms() const
{
    return hasterms;
}

CanonicalForm
CFIterator::coeff() const
{
    ASSERT( hasterms, "illegal term" );
    if ( ispoly )
        return cursor->coeff;
    else
        return data;
}

int
CFIterator::exp() const
{
    ASSERT( hasterms, "illegal term" );
    if ( ispoly )
        return cursor->exp;
    else
        return 0;
}