Documentation for sub indir

Documentation for sub indir, assembled from the following types:

role IO

From IO

(IO) sub indir

Defined as:

sub indir(IO() $path&code:$d = True:$r:$w:$x --> Mu)

Takes Callable &code and executes it after locally (to &code) changing $*CWD variable to an IO::Path object based on $path, optionally ensuring the new path passes several file tests. If $path is relative, it will be turned into an absolute path, even if an IO::Path object was given. NOTE: that this routine does NOT alter the process's current directory (see &*chdir). The $*CWD outside of the &code is not affected, even if &code explicitly assigns a new value to $*CWD.

Returns the return value of &code on success. On failure to successfully change $*CWD, returns Failure. WARNING: keep in mind that lazily evaluated things might end up NOT having the $*CWD set by indir in their dynamic scope by the time they're actually evaluated. Either ensure the generators have their $*CWD set or eagerly evaluate them before returning the results from indir:

say indir("/tmp"{
    gather { take ".".IO }
}.CWD# OUTPUT: «(/home/camelia)␤» 
say indir("/tmp"{
    eager gather { take ".".IO }
}.CWD# OUTPUT: «(/tmp)␤» 
say indir("/tmp"{
    my $cwd = $*CWD;
    gather { temp $*CWD = $cwdtake ".".IO }
}.CWD# OUTPUT: «(/tmp)␤» 

The routine's $path argument can be any object with an IO method that returns an IO::Path object. The available file tests are:

By default, only :d test is performed.

say $*CWD;                   # OUTPUT: «"/home/camelia".IO␤» 
indir '/tmp'{ say $*CWD }# OUTPUT: «"/tmp".IO␤» 
say $*CWD;                   # OUTPUT: «"/home/camelia".IO␤» 
indir '/not-there'{;};     # returns Failure; path does not exist