public VMException(FunctionDefn defn, string filename, Statement st, Exception inner)
: base("", inner)
{
this.defn = defn;
this.st = st;
this.filename = filename;
}
private void GetFreeVars(VM vm, Statement st, Stack<string> boundVars, Scope result)
{
// InternalCount and store the names defined by this statement
int nNewVars = 0;
foreach (string name in st.GetDefinedNames())
{
++nNewVars;
boundVars.Push(name);
}
// Iterate over all names used by expressions in the statement
foreach (string name in st.GetUsedNames())
{
// Is this not a boundVar, and not already marked as a free var
if (!boundVars.Contains(name) && !result.HasName(name))
{
// Throws an exception if the name is not found
HeronValue v = vm.LookupName(name);
result.Add(new VarDesc(name), v);
}
}
// Recurse over all sub statements, getting the free vars
foreach (Statement child in st.GetSubStatements())
GetFreeVars(vm, child, boundVars, result);
// Pop all variables added by this variable
for (int i = 0; i < nNewVars; ++i)
boundVars.Pop();
}
/// <summary>
/// Call this instead of "Stsatement.Eval()", this way you can set
/// breakpoints etc.
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
public void Eval(Statement statement)
{
CurrentStatement = statement;
statement.Eval(this);
}