Back in the days when everybody was building their own template interpolation code I used this little snippet This code interpolates the values from a vars hashref into the text string. I suspect that it can be improved but it worked for me for a long time - any suggestions welcome. 
  my $text =  'this is my text with a <%VAR%> to interpolate';
  my $vars = { 'VAR' => 'value taken from a data structure' };
  $_ = $text;
  while ( /<%(.+?)%>/g)
  {
    #print "$1\n";
    if (!defined $vars->{$1} )
    {
      $vars->{$1}  = 'undefined';
      $vars->{MESSAGE} .= "$1 undefined <br />\n"; ## keep a log of mi
+ssing variables
    }
  }
  $text =~ s/<%(.+?)%>/$vars->{$1}/g || warn("unable to substitute $1"
+);
  print qq{$text\n};

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In reply to Re: Invoke the Perl string interpolation engine on a string contained in a scalar variable. by localshop
in thread Invoke the Perl string interpolation engine on a string contained in a scalar variable. by ibm1620

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