From @briandfoy

tmpdir doesn't appear to change directories. This is probably why I
had the problem with https://rt-archive.perl.org/perl6/Ticket/Display.html?id=130454
(although I should have had a different error there).

It's not documented to do that in the various IO​::Spec modules, but I was
trying stuff in S16 to see what works. Should I be able to change the temporary
directory as S16 says, or is it forever fixed and should be documented as
read-only?

  my $dir = '/Users/brian';
  my $dir-io = $dir.IO;

  put "$dir is a dir​: " ~ $dir-io.d;
  put "$dir is readable​: " ~ $dir-io.r;
  put "$dir is executable​: " ~ $dir-io.x;
  put "$dir is writeable​: " ~ $dir-io.w;

  tmpdir( $dir )

It looks like everything should work, but it doesn't​:

  /Users/brian is a dir​: True
  /Users/brian is readable​: True
  /Users/brian is executable​: True
  /Users/brian is writeable​: True
  Cannot modify an immutable IO​::Path
  in block <unit> at /Volumes/Big Scratch/Dropbox/~~Writing/Perl
Writing/LearningPerl6/learning_perl_6/scratch/file_trials.p6 line 11

Or, assigning to it directly​:

  my $dir = '/Users/brian';
  my $dir-io = $dir.IO;

  put "$dir is a dir​: " ~ $dir-io.d;
  put "$dir is readable​: " ~ $dir-io.r;
  put "$dir is executable​: " ~ $dir-io.x;
  put "$dir is writeable​: " ~ $dir-io.w;

  $*TMPDIR = $dir;

It says I can't assign to $*TMPDIR. How is it that I can't assign to
dynamic variable? What's the point of it being dynamic if it can't change?

  Cannot modify an immutable IO​::Path
  in block <unit> at /Volumes/Big Scratch/Dropbox/~~Writing/Perl
Writing/LearningPerl6/learning_perl_6/scratch/file_trials.p6 line 11

Try it with my​:

  my $dir = '/Users/brian';
  my $dir-io = $dir.IO;

  put "$dir is a dir​: " ~ $dir-io.d;
  put "$dir is readable​: " ~ $dir-io.r;
  put "$dir is executable​: " ~ $dir-io.x;
  put "$dir is writeable​: " ~ $dir-io.w;

  my $*TMPDIR;

  tmpdir( $dir )

Now it's a different sort of error. This kinda makes sense because there's
nothing in $*TMPDIR and tmpdir expects IO​::Spec. But why is the error in
chdir and not something that catches that the argument wasn't IO​::Spec?

  /Users/brian is a dir​: True
  /Users/brian is readable​: True
  /Users/brian is executable​: True
  /Users/brian is writeable​: True
  No such method 'chdir' for invocant of type 'Any'
  in block <unit> at /Volumes/Big Scratch/Dropbox/~~Writing/Perl
Writing/LearningPerl6/learning_perl_6/scratch/file_trials.p6 line 13

Use temp instead, and it's a different error (despite that temp was
used for this purpose in S16)​:

  my $dir = '/Users/brian';
  my $dir-io = $dir.IO;

  put "$dir is a dir​: " ~ $dir-io.d;
  put "$dir is readable​: " ~ $dir-io.r;
  put "$dir is executable​: " ~ $dir-io.x;
  put "$dir is writeable​: " ~ $dir-io.w;

  temp $*TMPDIR;

  tmpdir( $dir )

Now it's a different sort of error​:

  /Users/brian is a dir​: True
  /Users/brian is readable​: True
  /Users/brian is executable​: True
  /Users/brian is writeable​: True
  Can only use 'temp' on a container
  in block <unit> at /Volumes/Big Scratch/Dropbox/~~Writing/Perl
Writing/LearningPerl6/learning_perl_6/scratch/file_trials.p6 line 11

From @zoffixznet

Thank you for the report. The issues in this ticket have been resolved​:

- "tmpdir doesn't appear to change directories"
  - &tmpdir has been removed
- "Should I be able to change the temporary directory"
  - Yes, by assigning to $*TMPDIR directly; simply do `my $*TMPDIR = 'foo/bar'.IO`.
  The issue that blocked assignment was fixed[^1] and tested[^2] in 2017.04 release
- "Can only use 'temp' on a container"
  - This too was fixed[^1] and tested[^2] in 2017.04 release

Side note​:
- "What's the point of it being dynamic if it can't change?"
  - There's no connection between dynamics and the ability to change
  them. Their point is scoping and not mutability; a change done to a dynamic
  var in some sub would still be visible up the call stack, which is why
  you'd usually use a `temp` or `my` on these global dynamic variables,
  like $*TMPDIR, to prevent your changes affecting other stuff. We do
  have immutable (or rather, containerless) dynamics (e.g. $*THREAD)
  and being unable to assign to them isn't a bug.

[1] rakudo/rakudo@b62d1a7
[2] Raku/roast@1d4e881

-- IO grant

The RT System itself - Status changed from 'new' to 'open'

@zoffixznet - Status changed from 'open' to 'resolved'