What other languages have features and/or libraries similar to Perl's format?

Question

I may be in the minority here, but I very much enjoy Perl's formats. I especially like being able to wrap a long piece of text within a column ("~~ ^<<<<<<<<<<<<<<<<" type stuff). Are there any other programming languages that have similar features, or libraries that implement similar features? I am especially interested in any libraries that implement something similar for Ruby, but I'm also curious about any other options.

Answer 1

There is the Lisp (format ...) function. It supports looping, conditionals, and a whole bunch of other fun stuff.

for example (copied from above link):

(defparameter *english-list*
  "~{~#[~;~a~;~a and ~a~:;~@{~a~#[~;, and ~:;, ~]~}~]~}")

(format nil *english-list* '())       ;' ==> ""
(format nil *english-list* '(1))      ;' ==> "1"
(format nil *english-list* '(1 2))    ;' ==> "1 and 2"
(format nil *english-list* '(1 2 3))  ;' ==> "1, 2, and 3"
(format nil *english-list* '(1 2 3 4));' ==> "1, 2, 3, and 4"

Answer 2

FormatR provides Perl-like formats for Ruby.

Here is an example from the documentation:

require "formatr"
include FormatR

top_ex = <<DOT
   Piggy Locations for @<< @#, @###
                     month, day, year

Number: location              toe size
-------------------------------------------
DOT

ex = <<TOD
@)      @<<<<<<<<<<<<<<<<       @#.##
num,    location,             toe_size
TOD

body_fmt = Format.new (top_ex, ex)

body_fmt.setPageLength(10)
num = 1

month = "Sep"
day = 18
year = 2001
["Market", "Home", "Eating Roast Beef", "Having None", "On the way home"].each {|location|
    toe_size = (num * 3.5)
    body_fmt.printFormat(binding)
    num += 1
}

Which produces:

   Piggy Locations for Sep 18, 2001

Number: location              toe size
-------------------------------------------
1)      Market                   3.50
2)      Home                     7.00
3)      Eating Roast Beef       10.50
4)      Having None             14.00
5)      On the way home         17.50

Answer 3

I seem to recall something similar in Fortran when I used it many years ago (however it may well have have been 3rd party library).

As for other options in Perl have a look at Perl6::Form.

The form function replaces format in Perl6. Damian Conway in "Perl Best Practices" recommends using Perl6::Form with Perl5 citing the following issues with format....

• statically defined
• rely on global variables for config & pkg vars for data they format on
• uses named filehandles (only)
• not recursive or re-entrant

Here is a Perl6::Form variation on the Ruby example by Robert Gamble....

use Perl6::Form;

my ( $month, $day, $year ) = qw'Sep 18 2001';
my ( $num, $numb, $location, $toe_size );

for ( "Market", "Home", "Eating Roast Beef", "Having None", "On the way home" ) {
    push @$numb,     ++$num;
    push @$location, $_;
    push @$toe_size, $num * 3.5;
}

print form 
    '   Piggy Locations for {>>>}{>>}, {<<<<}',
                          $month, $day, $year ,
    "",
    '  Number: location              toe size',
    '  --------------------------------------',
    '{]})      {[[[[[[[[[[[[[[[}       {].0} ',
     $numb,    $location,              $toe_size;

/I3az/