local function BasePartIterator(Table)
local Length = #Table;
local Thread = coroutine.create(function(_, Index)
if (not Index) then --// If we're not passed an Index, make it 1;
Index = 1;
else
Index = Index + 1; --// Otherwise increase it
end
for i = Index, Length do --// From the current Index to the Length
if (Table[i]:IsA("BasePart")) then
coroutine.yield(Table[i], i); --// These will be passed back again next iteration
end
end
--// If none is found then it'll return nil, nil stops the for loop iterating
end)
return function() --// Iterator
local Success, BasePart, Index = coroutine.resume(Thread)
return BasePart, Index;
end
end
local WorkspaceDescendants = workspace:GetDescendants();
for BasePart, IndexFound in BasePartIterator(WorkspaceDescendants) do
print(BasePart, IndexFound)
end
In this example from this tutorial, how come only baseparts are printed? Lets say its going through the coroutine and it happens to be something thats not a basepart. So the coroutine isn’t yielded as it didn’t pass the if check, then coroutine.resume didn’t return the correct basepart and index, index being nil as the coroutine wasn’t yielded. So if this is then returned, how come it doesn’t print it out in the output?
I changed the custom iterator loop at the bottom of the script to this:
Well, the for i = Index, Length do loop would just keep running in the same coroutine.resume until it either finishes without finding any BaseParts (at which point the iteration ends), or it finds a BasePart (at which point it will yield).
Ok well how come this doesn’t print a basepart and index:
local function BasePartIterator(Table)
local Length = #Table;
local Thread = coroutine.create(function(_, Index)
if (not Index) then --// If we're not passed an Index, make it 1;
Index = 1;
else
Index = Index + 1; --// Otherwise increase it
end
for i = Index, Length do --// From the current Index to the Length
if (Table[i]:IsA("BasePart")) then
coroutine.yield(Table[i], i); --// These will be passed back again next iteration
end
end
--// If none is found then it'll return nil, nil stops the for loop iterating
end)
return function() --// Iterator
local Success, BasePart, Index = coroutine.resume(Thread)
return BasePart, Index;
end
end
local WorkspaceDescendants = workspace:GetDescendants();
local BasePart, IndexFound = BasePartIterator(WorkspaceDescendants)
print(BasePart, IndexFound)
--for BasePart, IndexFound in BasePartIterator(WorkspaceDescendants) do
--print(BasePart, IndexFound)
--end
Because for loops are fancy and special and do things behind the scenes for you, like repeatedly calling the function that you give it until said function returns nil.
