in reply to Re: while(<>) in perl 5.22
in thread while(<>) in perl 5.22

Neither result is consistent with my understanding of the 5.22 documentation. 
    while (<>) {
        ...                     # code for each line
    }

is equivalent to the following Perl-like pseudo code:

    unshift(@ARGV, '-') unless @ARGV;
    while ($ARGV = shift) {
        open(ARGV, $ARGV);
        while (<ARGV>) {
            ...         # code for each line
        }
    }

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I would expect the open to fail silently.(There is no explicit test for errors.) The read on the unopened filehandle should return a false value. The loop would terminate without ever executing the print statement.

Bill

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Re^3: while(<>) in perl 5.22
by choroba (Cardinal) on Nov 14, 2016 at 23:25 UTC
    The documentation also says there's a difference, and you can easily see there is: 
    ~ $ perl -e '1 while <>' non-existent-file
Can't open non-existent-file: No such file or directory at -e line 1.

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    ($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

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