private static VariableContext DeconstructBinary(
BinaryOperation op, SymbolMap map, VariableContext output)
{
var leftMapChild = (SymbolMap)map.ChildOrDefault(0);
var rightMapChild = (SymbolMap)map.ChildOrDefault(1);
output = Deconstruct(op.Operand1, leftMapChild, output);
output = Deconstruct(op.Operand2, rightMapChild, output);
if (leftMapChild == null && rightMapChild == null && map.Value.HasName)
{
output.Define(map.Value.Name, op);
}
return(output);
}
private static VariableContext DeconstructUnary(
UnaryOperation op, SymbolMap map, VariableContext output)
{
var mapChild = (SymbolMap)map.ChildOrDefault(0);
if (mapChild != null)
{
output = Deconstruct(op.Child, mapChild, output);
}
if (mapChild == null && map.Value.HasName)
{
output.Define(map.Value.Name, op);
}
return(output);
}
public static SymbolicTransform New(
BasicSymbolicConstraint constraint,
SymbolMap inputMap,
Function outputFunction)
{
var inputContext = inputMap.GenerateContext();
if (!outputFunction.ContainsVariables(inputContext))
{
throw new InvalidTransformException(
$"'{nameof(inputMap)}' contains variable names that do not exist in '{nameof(outputFunction)}'");
}
var deconstructor = new SymbolicDeconstructor(inputMap);
return(new SymbolicTransform(constraint, deconstructor, outputFunction));
}
private static VariableContext Deconstruct(
ISymbol expression, SymbolMap map, VariableContext output)
{
if (map == null)
{
return(output);
}
if (expression.Type.IsBinaryOperation())
{
var binaryExp = expression as BinaryOperation;
return(DeconstructBinary(binaryExp, map, output));
}
if (expression.Type.IsUnaryOperation())
{
var unaryExp = expression as UnaryOperation;
return(DeconstructUnary(unaryExp, map, output));
}
if (expression.Type.IsValue())
{
if (map.HasChildren)
{
throw new InvalidOperationException(
"symbol map attempted to traverse expression tree too deep");
}
if (map.Value.HasName)
{
output.Define(map.Value.Name, expression);
}
return(output);
}
throw new NotImplementedException(
"Attempted to traverse unsupported expression type: " +
expression.Type.ToString());
}
public SymbolicDeconstructor(SymbolMap map)
{
_map = map;
}
