A simple program that assigns to $_ using . : Special Variables « Language Basics « Perl






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  2. Language Basics
  3. Special Variables

A simple program that assigns to $_ using .

   
#!/usr/local/bin/perl 

while (<STDIN>) { 
    ($first) = split (//, $_); 
    print ("$first\n"); 
}








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35.$" is the separator
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37.$(dollar), is the separator
38.$MATCH = $&
39.$SIG{__DIE__}
40.$SIG{__WARN__} = 'IGNORE';
41.$SIG{__WARN__} = sub {die "Warning: $_[0]"};
42.$\ is 'END_OF_OUTPUT'
43.$^ is the format header
44.$^O stores the name of the operating system
45.$^S: is inside eval
46.$^W: Check the '-w switch'
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48.$_ for print function
49.$_ stores the user input
50.$~ is the format
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