runST package:array
A safe way to create and work with a mutable array before returning an
immutable array for later perusal. This function avoids copying the
array before returning it - it uses unsafeFreeze internally,
but this wrapper is a safe interface to that function.
A safe way to create and work with an unboxed mutable array before
returning an immutable array for later perusal. This function avoids
copying the array before returning it - it uses unsafeFreeze
internally, but this wrapper is a safe interface to that function.