Perl Module File::Modified Files parameter

Question

The documentation of File::Modified says:

my $d = File::Modified->new(files=>['Import.cfg','Export.cfg']);

The files parameter looks to me as being an array.

Why can I not directly hand over an array?

my $d = File::Modified->new(files=>@array);

This creates a runtime error.

Does this answer your question? [Passing array to subroutine Perl](https://stackoverflow.com/questions/72380485/passing-array-to-subroutine-perl) — tobyink, Aug 30 '23 at 12:58
`files=>@array` would results in `files=>'Import.cfg', 'Export.cfg'=>undef` — ikegami, Aug 30 '23 at 13:39

toolic · Accepted Answer · 2023-08-30T13:15:39.673

The files parameter is not an array; it is a reference to an array.
The File::Modified POD says:

Files, which takes an array reference to the filenames to watch.

This is why you can not simply pass an array variable like that.

The square brackets create a reference to an array, which is different from an array.

As the perlref document shows, one way to take a reference to an array is to use the backslash:

my $d = File::Modified->new(files => \@array);

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