I'm working through some optional exercises from a recent Perl class. I'm stumped by this one: This code works fine: 

my(@input_array) =();

chomp(@input_array = <STDIN>);

#===== Search for a e i o and u (case insensitive)
foreach $_ (@input_array)
{
  if ($_ =~ /a/i && /e/i && /i/i && /o/i && /u/i)
  {
    print $_, "\n";
  }
}

[download]

This code fails with "Use of uninitialized value in pattern match (m//) at ./match4 line 19, <STDIN> line 3.": 

my(@input_array) =();
my($one_line) = '';

chomp(@input_array = <STDIN>);

#===== Search for a e i o and u (case insensitive)
foreach $one_line(@input_array)
{
  if ($one_line =~ /a/i && /e/i && /i/i && /o/i && /u/i)
  {
    print $one_line, "\n";
  }
}

[download]
What gives? Isn't it just about the same exact code?

For some reason, I keep getting these "uninitialized value" warnings on my OSX machine when running examples that gave me no errors on the Unix machine we used for my class. Something is different between the two Unix implementations, but I'm not sure what I'm doing wrong.

Thanks!

Charles Thomas
Madison, WI

In reply to $_ works, $my_variable doesn't? by C_T

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