carlriz has asked for the wisdom of the Perl Monks concerning the following question:

So, here's what I am trying to do. I am trying to obtain information about a computer and print it to a file. My approach is to use 'qq//' to put and format the information collected and then print it as a block to a file. I wanted to issue a function call to neatly place stars in the document to separate each data segment (see my failed print "*"x 80 line). How do you make a function call in qq//? 

 
sub find_system_info {
    my $file_handle = shift;

    my $kernal_release = qx/uname -r/;
    my $partition_list = qx/fdisk/;
    my $disk_space = qx/df/;
    my $active_interfaces = qx/ifconfig/;

    my $output_basic = qq(                                            
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+                                          
        'print "*" x80'                                               
+                                                                     
+                                          
        Kernal Release: $kernal_release                               
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+                                          
                                                                      
+                                                               
`       Partition List:                                               
+                                                                     
+                                          
                                                                      
+                                                                     
+                                          
        $partition_list                                               
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        Disk Space:                                                   
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        $disk_space                                                   
+                                                                     
+                                          
                                                                      
+                                                                     
+                                                                     
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+                                 
        Network Interfaces:                                           
+                                                                     
+                                          
        $active_interfaces                                            
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+                                                                     
+                                                                     
+                                                                     
+                                                                     
+                                                                     
+                                                                     
+                                                                     
+                                                                     
+                );
print $file_handle  $output_basic;
}

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Re: Function call inside qq//
by choroba (Cardinal) on Apr 02, 2014 at 13:44 UTC
    You can use the "pram" operator: 
    $output = qq(
    @{[ '*' x 80 ]}
);

    [download]

    but it might be easier to assign the start to a variable before creating the output: 

    my $STARS = '*' x 80;
my $output = qq(
    $STARS
);

    [download]

    Using print would print the line of stars in the moment of assignment, and insert the return value of print (hopefully 1) into the created string.

    لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ
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Re: Function call inside qq//
by AnomalousMonk (Archbishop) on Apr 02, 2014 at 17:35 UTC

    In addition to the 'pram' operator (also known as the Baby Cart From Hell operator), there's something like: 

    c:\@Work\Perl\monks>perl -wMstrict -le
"sub stars { return \ ('*' x $_[0]); }
 ;;
 my $str = qq{foo-${ stars(5) }-bar};
 print qq{'$str'};
"
'foo-*****-bar'

    [download]

    But why bother? Just use good old sprintf; that's what it's there for. 

    c:\@Work\Perl\monks>perl -wMstrict -le
"sub stars { return '*' x $_[0]; }
 ;;
 my $str = sprintf 'foo%s%sbar', stars(5), '=' x 7;
 print qq{'$str'};
"
'foo*****=======bar'

    [download]

    Update: Added sprintf example, Baby Cart WP link.

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