protected override Expression VisitConstant(ConstantExpression node)
{
switch (node.Value)
{
case null:
case string _:
return(node);
default:
if (node.Type.GetTypeInfo().IsValueType)
{
return(node);
}
break;
}
UnaryExpression unaryExpression;
if (_templateClosure.TryGetKeyByValue(node.Value, out var existingKey))
{
unaryExpression =
Expression.Convert(
Expression.ArrayIndex(_templateClosureArg, Expression.Constant(existingKey)),
node.Type);
return(unaryExpression);
}
var key = _templateClosure.CurrentIndex;
_templateClosure[key] = node.Value;
var accessor = Expression.ArrayIndex(_templateClosureArg, Expression.Constant(key));
unaryExpression = Expression.Convert(accessor, node.Type);
return(unaryExpression);
}
