public override ReturnValue Value(Binding b)
{
try {
return b.ValueFor(name);
} catch (KeyNotFoundException /* unused */) {
return new ReturnValue();
}
}
public override ReturnValue Value(Binding b)
{
if (expr != null) {
if (b.Set (name, expr)) {
ReturnValue ret = expr.Value (b);
return new ReturnValue (name + " = " + ret);
} else {
return new ReturnValue (name + " = " + b.ValueFor (name));
}
}
return new ReturnValue (name + " = undefined");
}
public override ReturnValue Value(Binding binding)
{
ReturnValue ra = a.Value(binding);
ReturnValue rb = b.Value(binding);
if (!ra.Defined() || !rb.Defined()) {
return new ReturnValue();
}
if (op == '+') {
return new ReturnValue(ra.Value() + rb.Value());
} else if (op == '-') {
return new ReturnValue(ra.Value() - rb.Value());
} else if (op == '*') {
return new ReturnValue(ra.Value() * rb.Value());
} else if (op == '/') {
return new ReturnValue(ra.Value() / rb.Value());
} else {
throw new ParserException("Unknown operator: " + op);
}
}
public abstract ReturnValue Value(Binding b);
public override ReturnValue Value(Binding b)
{
return new ReturnValue(val);
}
public Calculator(Binding b)
{
this.binding = b;
}