private SolverNode CloseVariable(IVariable variable,
IAbstractExpr expression,
AbstractConstraint sourceConstraintToBeRemoved)
{
//var foldingVisitor = new ConstantFoldingVisitor();
var foldingVisitor = new PolynomialFoldingVisitor();
expression = expression.Accept(foldingVisitor);
// Rewrite all constraints
//var rewriter = new RewritingVisitor(
// new Dictionary<IAbstractExpr, IAbstractExpr> { { variable, expression } });
var rewriter = new RewritingVisitor(variable, expression);
IEnumerable<AbstractConstraint> rewrittenConstraints =
Constraints.Except(sourceConstraintToBeRemoved)
.Select(c => c.Accept(rewriter, Ig.nore));
// Create new variable->value knowledge or new backsubstition.
var newBacksubstitutions = new Dictionary<IVariable, AbstractClosedVariable>(ClosedVariables) {{
variable, expression is IConstant
? (AbstractClosedVariable)
new VariableWithValue(variable, ((IConstant) expression).Value)
: new VariableWithBacksubstitution(variable, expression)
}};
// Create new node.
return new SolverNode(rewrittenConstraints, newBacksubstitutions, this);
}
private IAbstractExpr Fold(IAbstractExpr expr)
{
return expr.Accept(new PolynomialFoldingVisitor(), Ig.nore);
//return expr.Accept(new PolynomialFoldingVisitor(), 0);
}