go/doc/next/6-stdlib/3-iter.md

Iterators

The new [iter] package provides the basic definitions for working with user-defined iterators.

The [slices] package adds several functions that work with iterators:

• All returns an iterator over slice indexes and values.
• Values returns an iterator over slice elements.
• Backward returns an iterator that loops over a slice backward.
• Collect collects values from an iterator into a new slice.
• AppendSeq appends values from an iterator to an existing slice.
• Sorted collects values from an iterator into a new slice, and then sorts the slice.
• SortedFunc is like Sorted but with a comparison function.
• SortedStableFunc is like SortFunc but uses a stable sort algorithm.
• Chunk returns an iterator over consecutive sub-slices of up to n elements of a slice.

The [maps] package adds several functions that work with iterators:

• All returns an iterator over key-value pairs from m.
• Keys returns an iterator over keys in m.
• Values returns an iterator over values in m.
• Insert adds the key-value pairs from seq to m.
• Collect collects key-value pairs from seq into a new map and returns it.