public static void Setup()
{
var invo = new InvokeableItem();
var fn = new Invokeable
{
ReturnType = ItemType.Space,
Demands = InvokeableUtils.MakeDemands(
InvokeableUtils.DemandType(0, ItemType.List),
args => (args[0] as ListItem).Expression.HasEvenLength(),
args => (args[0] as ListItem).Expression
.GroupingSelect(2)
.All(pair => pair[0].ItemType == ItemType.Symbol)),
Function = (space, args) =>
{
var newSpace = new SymbolSpace(space);
var symbolValuePairs = (args[0] as ListItem).Expression.GroupingSelect(2);
foreach (var pair in symbolValuePairs)
{
var symbol = pair[0] as SymbolItem;
newSpace.Bind(symbol.Name, pair[1]);
}
return(new SymbolSpaceItem(newSpace));
}
};
invo.AddInvokeable(fn);
globalSpace.Bind("make-space", invo);
}
public static void Setup()
{
const int typeIndex = 0;
const int paramsIndex = 1;
const int bodyIndex = 2;
Func <Item, List <Tuple <Item, Item> > > groupArguments = l =>
(l as ListItem).Expression
.GroupingSelect(2, xs => new Tuple <Item, Item>(xs[0], xs[1]));
Func <List <Item>, ListItem> getParams = args => (args[paramsIndex] as ListItem);
// now to the meat of things
var invo = new InvokeableItem();
var fn = new Invokeable
{
ReturnType = ItemType.Invokeable,
Demands = InvokeableUtils.MakeDemands(
InvokeableUtils.DemandTypes(ItemType.Type, ItemType.List, ItemType.List),
args => args.Count == 3,
args => getParams(args).Expression.HasEvenLength(),
args => groupArguments(getParams(args)).All(pair =>
pair.Item1.ItemType == ItemType.Symbol &&
pair.Item2.ItemType == ItemType.Type)
),
Function = (space, args) =>
{
var returnType = args[typeIndex] as TypeItem;
var argumentList = groupArguments(args[paramsIndex]);
var body = args[bodyIndex] as ListItem;
var argumentTypes =
argumentList
.Select(argument => (argument.Item2 as TypeItem).Type)
.ToArray();
var resultingInvokeable = new InvokeableItem();
resultingInvokeable.AddInvokeable(new Invokeable()
{
ReturnType = returnType.Type,
Demands = InvokeableUtils.MakeDemands(InvokeableUtils.DemandTypes(argumentTypes)),
// create symbol space,
// bind fnargs,
// evaluate body with new symbol space
Function = (fnspace, fnargs) => {
var newSpace = new SymbolSpace(space);
for (var index = 0; index < fnargs.Count; index++)
{
newSpace.Bind(
(argumentList[index].Item1 as SymbolItem).Name,
fnargs[index]);
}
body = body.Unquote() as ListItem;
return(body.Evaluate(newSpace));
}
});
return(resultingInvokeable);
}
};
invo.AddInvokeable(fn);
globalSpace.Bind("=>", invo);
}