private static BoundScope CreateParentScopes(BoundGlobalScope previous)
{
// create scopes in the opposite order
// submission 3 => submission 2 => submission 1
var stack = new Stack <BoundGlobalScope>();
while (previous != null)
{
stack.Push(previous);
previous = previous.Previous;
}
BoundScope parent = null;
while (stack.Count > 0)
{
previous = stack.Pop();
var scope = new BoundScope(parent);
foreach (var variable in previous.Variables)
{
scope.TryDeclare(variable);
}
parent = scope;
}
return(parent);
}
/// <summary>
/// Block statements need to be bound for evaluation. Everytime statement is nested, we need to update the scope
/// </summary>
/// <param name="syntax"></param>
/// <returns></returns>
private BoundBlockStatement BindBlockStatement(BlockStatementSyntax syntax)
{
var statements = ImmutableArray.CreateBuilder <BoundStatement>();
_scope = new BoundScope(_scope);
foreach (var statementSyntax in syntax.Statements)
{
var statement = BindStatement(statementSyntax);
statements.Add(statement);
}
_scope = _scope.Parent;
return(new BoundBlockStatement(statements.ToImmutable()));
}
public Binder(BoundScope parent)
{
_scope = new BoundScope(parent);
}
public BoundScope(BoundScope parent)
{
Parent = parent;
}