public override object Execute(List arguments, ValueEnvironment environment)
{
ValueEnvironment newenv;
newenv = MakeEnvironment((List)arguments.First, environment);
FSubrProgN progn = new FSubrProgN();
return(progn.Execute(arguments.Next, newenv));
}
public override object Execute(List arguments, ValueEnvironment environment)
{
if (Predicates.IsFalse(Machine.Evaluate(arguments.First, environment)))
{
List elseexpr = arguments.Next.Next;
FSubrProgN progn = new FSubrProgN();
return(progn.Execute(elseexpr, environment));
}
return(Machine.Evaluate(arguments.Next.First, environment));
}
public override object Execute(List arguments, ValueEnvironment env)
{
while (!Predicates.IsNil(arguments))
{
List pair = (List)arguments.First;
object condition;
condition = pair.First;
if (!Predicates.IsFalse(Machine.Evaluate(condition, env)))
{
FSubrProgN progn = new FSubrProgN();
return(progn.Execute(pair.Next, env));
}
arguments = arguments.Next;
}
return(null);
}
internal object ExecuteBody(ValueEnvironment environment)
{
FSubrProgN progn = new FSubrProgN();
return(progn.Execute(this.body, environment));
}
