// --------------------------------------------------------------------------
// Section Using immutable data structures
// NOTE: The following two functions aren't included in the book text
// Returns places as an immutable list
static IEnumerable <string> LoadImmutablePlaces()
{
return(FuncList.Cons("Cambridge", FuncList.Cons("Grantchester",
FuncList.Cons("New York", FuncList.Cons("Prague",
FuncList.Cons("Seattle", FuncList.Empty <string>()))))));
}
public override TranslationState VisitTextPart(TextPart part, TranslationState ctx)
{
ctx.Result = FuncList.Cons(new TextElement(part.Text, ctx.Rect), FuncList.Empty <ScreenElement>());
return(ctx);
}
static void AggregateMain()
{
// Initialize a sample list
var list = FuncList.Cons(1, FuncList.Cons(2, FuncList.Cons(3,
FuncList.Cons(4, FuncList.Cons(5, FuncList.Empty <int>())))));
// Multiply and sum elements
// the first call prints 15, the second 120
Console.WriteLine(AggregateList(list, 0, Add));
Console.WriteLine(AggregateList(list, 1, Mul));
}
public override TranslationState VisitImagePart(ImagePart part, TranslationState ctx)
{
ctx.Result = FuncList.Cons(new ImageElement(part.Url, ctx.Rect), FuncList.Empty <ScreenElement>());
return(ctx);
}
static void ListsMain()
{
// Create a list storing 1,2,3,4,5
var list = FuncList.Cons(1, FuncList.Cons(2, FuncList.Cons(3,
FuncList.Cons(4, FuncList.Cons(5, FuncList.Empty <int>())))));
// Calculates and prints "15"
int sum = SumList(list);
Console.WriteLine(sum);
}