in reply to inplace file editing

I think the difference does not have to do with the use of $^I, but with how $/=undef behaves when reading from the magic <> file handle. The following program: 
$^I="";
undef $/;
while(<>) { print "hello:\n" }

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Behaves the same if I comment out the $^I line: it prints "hello" twice, except that when $^I="" it is printed to the file I give as argument, obliterating it. Printing $_ on each iteration shows that $_ contains '' (empty string) on the second iteration, so my guess is that setting $/ to undef somehow changes the way in which perl reads from <>, but I don't really have an answer...

--ZZamboni

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Re: Re: inplace file editing
by Anonymous Monk on Jun 11, 2001 at 11:40 UTC
    sorry, what i meant to say was 
    $ARGV[0]="test";
$^I="";
undef $/;

while(<>) { print STDOUT "hello\n" }

    [download]
    (which stops hello getting printed to the file)...but it still prints twice. can ANYONE help?
[reply]
[d/l]

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