Re: "my $filehandle" scoping strange problem

B::Deparse is your friend in strange syntax corners.

$ perl -MO=Deparse,-p,-q
# . . . your first example here
^D
unless (open(my $fh, '<f1.txt')) {
    do {
        print(STDERR "can't open <f1.txt, but nevermind, I'll try f2.t
+xt\n");
        (open($fh, '<f2.txt') or die(q[still can't...]));
    };
}
print(<$fh>);
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So you can see now that $fh is scoped to the unless block that's been implicitly created.

Update: Not that that's not a little wierd, mind you. After looking at it a second time it's slightly surprising.

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Re^2: "my $filehandle" scoping strange problem by vkon (Curate) on Apr 14, 2006 at 12:56 UTC
Given, as you said, $fh is scoped to the unless block, why the almighty DWIMery allows to use $fh afterwards within a scope of `use strict;`??	[reply] [d/l]
Re^3: "my $filehandle" scoping strange problem by Fletch (Bishop) on Apr 14, 2006 at 13:30 UTC
It doesn't. Add a `-Mstrict` or `use strict;` and it complains. `$ perl -MO=Deparse,-p,-q use strict; open my $fh, "<f1.txt" or do { print STDERR "can't open <f1.txt, but nevermind, I'll try f2.txt\n +"; open $fh, "<f2.txt" or die "still can't..."; }; print <$fh>; ^D Global symbol "$fh" requires explicit package name at - line 5. - had compilation errors. use strict 'refs'; unless (open(my $fh, '<f1.txt')) { do { print(STDERR "can't open <f1.txt, but nevermind, I'll try f2.t +xt\n"); (open(${'fh'}, '<f2.txt') or die(q[still can't...])); }; } print(<$fh>);` [download]	[reply] [d/l] [select]
Re^4: "my $filehandle" scoping strange problem by vkon (Curate) on Apr 14, 2006 at 13:54 UTC
Thanks. Actually my problem was due to yet another $fh in outer block. My larger script, which uses strict (let strict's days will be countless:) contained another declaration of $fh, so within `open my $fh ......` outer $fh come into play ..... Problem is solved...	[reply] [d/l]