private static BoundScope CreateParentScopes(BoundGlobalScope previous)
{
// submission 3 => submission 2 => submission 1
var stack = new Stack <BoundGlobalScope>();
while (previous != null)
{
stack.Push(previous);
previous = previous.Previous;
}
// submission 1 => submission 2 => submission 3
BoundScope parent = null;
while (stack.Count > 0)
{
previous = stack.Pop();
var scope = new BoundScope(parent);
foreach (var v in previous.Variables)
{
scope.TryDeclare(v);
}
parent = scope;
}
return(parent);
}
public BoundGlobalScope(BoundGlobalScope previous, ImmutableArray <Diagnostic> diagnostics, ImmutableArray <VariableSymbol> variables, BoundStatement statement)
{
Statement = statement;
Variables = variables;
Diagnostics = diagnostics;
Previous = previous;
}
public static BoundGlobalScope BindGlobalScope(BoundGlobalScope previous, CompilationUnitSyntax syntax)
{
var parentScope = CreateParentScopes(previous);
var binder = new Binder(parentScope);
var boundStatement = binder.BindStatement(syntax.Statement);
var variables = binder._scope.GetDeclaredVariables();
var diagnostics = binder.Diagnostics.ToImmutableArray();
//Since in CLI, the variables from different lines are chaining (nested)
//we need to chain the diagnostics too.
//otherwise, statements like a=b will give error, but
//when we reference a again, it will not have the same error
if (previous != null)
{
diagnostics = diagnostics.InsertRange(0, previous.Diagnostics);
}
return(new BoundGlobalScope(previous, diagnostics, variables, boundStatement));
}