Stream.junk has no effect on a Stream.of_channel until we use Stream.next

[vicuna]

Original bug ID: 7769
Reporter: Michael_Perin
Assigned to: @nojb
Status: resolved (set by @nojb on 2018-04-11T12:27:13Z)
Resolution: fixed
Priority: normal
Severity: minor
Platform: Intel Core i7
OS: Mac OS
OS Version: 10.13.3
Version: 4.02.3
Category: standard library
Monitored by: @nojb

Bug description

On a stream made from a file, using Stream.of_channel, the function Stream.junk : 'a Stream.t -> unit
which should "Remove the first element of the stream, possibly unfreezing it before."
has no effect until we use Stream.next.

It behaves normally on a stream made from a string.

Here is a piece of code that demonstrates this strange behaviour.

Steps to reproduce

#create a file
echo "abcdefghijklmnopqrstuvwxyz" > alphabet.txt

execute the uploaded file

ocaml demo.ml

File attachments

• demo.ml

[vicuna]

Comment author: @nojb

Reproduced on trunk.

[vicuna]

Comment author: @nojb

Potential fix in #1714

[vicuna]

Comment author: @nojb

PR merged, will be in 4.07.