public override string AST(int depth = 0)
{
var sb = new StringBuilder($"{Spaces(depth)}[{Name}\n" +
(Type != null ? $"{Type.AST(depth + 1)}" : "") +
$"{Id.AST(depth + 1)}");
foreach (var s in Parameters)
{
sb.Append(s.AST(depth + 1));
}
sb.Append($"{Statement.AST(depth + 1)}{Spaces(depth)}]\n");
return(sb.ToString());
}