diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/gleam/iterator.gleam | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/src/gleam/iterator.gleam b/src/gleam/iterator.gleam index 8a4410d..efde4f5 100644 --- a/src/gleam/iterator.gleam +++ b/src/gleam/iterator.gleam @@ -2,24 +2,25 @@ import gleam/list // Internal private representation of an Iterator type Action(element) { - // Improper dancing in the middle of the street - // Improper dancing in the middle of the street - // Improper dancing in the middle of the street - // Somebody better notify the chief of police Stop Continue(element, fn() -> Action(element)) } -// Yes! -// Wrapper to hide the internal representation +/// An iterator is a lazily evaluated sequence of element. +/// +/// Iterators are useful when working with collections that are too large to +/// fit in memory (or those that are infinite in size) as they only require the +/// elements currently being processed to be in memory. +/// +/// As a lazy data structure no work is done when an iterator is filters, +/// mapped, etc, instead a new iterator is returned with these transformations +/// applied to the stream. Once the stream has all the required transformations +/// applied it can be evaluated using functions such as `fold` and `take`. +/// pub opaque type Iterator(element) { Iterator(thunk: fn() -> Action(element)) } -pub fn identity(x) { - x -} - // Public API for iteration pub type Step(element, acc) { Next(element, acc) |