SPUG: Problem deleting files

Daniel Chetlin daniel at chetlin.com
Fri Dec 1 11:44:38 CST 2000

On Fri, Dec 01, 2000 at 08:34:00AM -0800, Scott Blachowicz wrote:
> Yes, unlink takes a LIST of files and the <$oldfiles> should return a
> list of filenames matching the glob pattern contained in the $oldfiles
> var.

Because `<>' is overloaded in Perl, `<$oldfiles>' won't do what you'd
expect here.

> It must not to variable expansion inside the globbing brackets, so you
> have to the expansion yourself by using "eval".

Well, no, not exactly. See perlop:

    If angle brackets contain is a simple scalar variable (e.g.,
    <$foo>), then that variable contains the name of the filehandle to
    input from, or its typeglob, or a reference to the same. For

        $fh = \*STDIN;
        $line = <$fh>;

    If what's within the angle brackets is neither a filehandle nor a
    simple scalar variable containing a filehandle name, typeglob, or
    typeglob reference, it is interpreted as a filename pattern to be
    globbed, and either a list of filenames or the next filename in the
    list is returned, depending on context. This distinction is
    determined on syntactic grounds alone. That means '<$x>' is always a
    readline() from an indirect handle, but '<$hash{key}>' is always a
    glob(). That's because $x is a simple scalar variable, but
    '$hash{key}' is not--it's a hash element.

    One level of double-quote interpretation is done first, but you
    can't say '<$foo>' because that's an indirect filehandle as
    explained in the previous paragraph. (In older versions of Perl,
    programmers would insert curly brackets to force interpretation as a
    filename glob: '<${foo}>'.  These days, it's considered cleaner to
    call the internal function directly as 'glob($foo)', which is
    probably the right way to have done it in the first place.)

I haven't used the `<>' form of globbing in years. Come to think of it,
I haven't used globbing in Perl at all in years. Generally readdir
and/or File::Find are much more robust, predictable, easy to use, and


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