### Iterators

The new [`iter` package](/pkg/iter/) provides the basic definitions for

pkg iter, func Pull2[$0 interface{}, $1 interface{}](Seq2[$0, $1]) (func() ($0, $1, bool), func()) #61897
pkg iter, func Pull[$0 interface{}](Seq[$0]) (func() ($0, bool), func()) #61897
pkg iter, type Seq2[$0 interface{}, $1 interface{}] func(func($0, $1) bool) #61897

<!-- see ../../3-iter.md -->...

must either all be present or all be absent. If present, each name
stands for one item (parameter or result) of the specified type and
all non-<a href="#Blank_identifier">blank</a> names in the signature
must be <a href="#Uniqueness_of_identifiers">unique</a>.
If absent, each type stands for one item of that type.
Parameter and result
lists are always parenthesized except that if there is exactly