The old-fashoned way to do this is with format, and it may be the best.

To do it with printf formats, you will need to construct the format string on the fly, taking account of the length of what you want to print.

Another way I'd consider is with substr: 

my $line = ' ' x 200;
my $cols = {
    0    =>   \$var1,
    19   =>   \$var2,
    179  =>   \$var3,
    199  =>   \$var4
};
for (keys %$cols) {
    my $val = ${$cols->{$_}};
    substr $line, $_, length($val), $val;
}
print MERGE $line, $/;

[download]
That doesn't conform to the formats you wanted for the indifidual variables, but an extra hash on the same keys and with format strings as values could provide that to my $val = sprintf ... .

Your $varN variables want to be an array, but I assume the names have been changed to protect the guilty ;-)

After Compline,
Zaxo

In reply to Re: Formatting an output with printf by Zaxo
in thread Formatting an output with printf by fiddler42

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.