# How would this Perl script look in Ruby? **URL:** \ **Category:** Ruby\ **Created:** [August 28, 2008, 2:28pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109 "2008-08-28T14:28:12Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [August 28, 2008, 2:28pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/1 "2008-08-28T14:28:12Z")
Can somebody please me tell the way to write this script in Ruby? ;--------------------------------------- #!/bin/env perl use strict; use Data::Dumper; #; define some message templates here my $message\_templates = [ ‘adm has _QTY_ _CAR_ cars’, ‘ssn had _QTY_ _CAR_ cars’, ]; #; value map my %value\_map = ( ‘_CAR_’ =\> { ‘order’ =\> ‘rand’, ‘vals’ =\> [qw(bentley merc bmw audi porsche ford honda lexus)] }, ‘_QTY_’ =\> { ‘order’ =\> ‘rand’, ‘vals’ =\> [1…10] } ); # using 'random\_msg\_stub and val generators from %value\_map sub get\_next\_random\_msg { my ($next\_msg, $val\_map) = @\_; ``` my $m = &$next_msg(); while (my($vk, $v) = each (%value_map)) { my ($nval) = $v->{gen}->(); $m =~ s/$vk/$nval/g; } $m; ``` } # return $arrya[$last + 1] elem of array; $last is remembered across invocations sub get\_seq\_val\_generator { my $a = $\_[0]; my $last = 0; return sub { $last = 0 if ($last == scalar @$a); $$a[$last++]; }; } # return random elem of array sub get\_random\_val\_generator { my $arr = shift; return sub { return $arr-\>[rand @$arr] }; } #; let’s generate value generator foreach value in 'value\_map while (my($vk, $v) = each (%value\_map)) { if ($v-\>{order} eq ‘seq’) { $v-\>{gen} = get\_seq\_val\_generator($v-\>{vals}); } elsif ($v-\>{order} eq ‘rand’) { $v-\>{gen} = get\_random\_val\_generator($v-\>{vals}); } else { die “Invalid value order in value\_map\n”; } } my ($get\_next\_random\_msg\_stub) = get\_random\_val\_generator($message\_templates); while (1) { print get\_next\_random\_msg($get\_next\_random\_msg\_stub, %value\_map), “\n\n”; } 1; ;-------------------------------------------------- thanks in advance. ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [August 28, 2008, 2:34pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/2 "2008-08-28T14:34:28Z")
Why don’t you show us what you have, and where you are stuck, rather than us translating it for you in it’s entirety. On Thu, Aug 28, 2008 at 09:23:30PM +0900, Avinash M. wrote: > ``` > 'adm has _QTY_ _CAR_ cars', > 'order' => 'rand', > my ($nval) = $v->{gen}->(); > return sub { > > ``` > > ;-------------------------------------------------- > > ## thanks in advance. > > Posted via [http://www.ruby-forum.com/](http://www.ruby-forum.com/). – nathan nathan\_at\_nathanpowell\_dot\_org At this point, anyone proposing to run Windows on servers should be prepared to explain what they know about servers that Google, Yahoo, and Amazon don’t. ~ Paul Graham ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [August 28, 2008, 2:42pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/3 "2008-08-28T14:42:26Z")
Nathan Powell wrote: > Why don’t you show us what you have, and where you are stuck, rather > than us translating it for you in it’s entirety. sorry about that. things I would like to know are: 1. How would we write following method? the one which takes an array and return subref (whatever equivalent in Ruby) something like this(in perl) sub get\_random\_val\_generator { my $arr = shift; return sub { return $arr-\>[rand @$arr] }; } 2. How to store these references(subrefs) in a hash or some variable? 3. How would you do(approach) this in Ruby(the script)? Since I know very little about Ruby so I don’t the construct used for this purpose? ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [August 28, 2008, 2:58pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/4 "2008-08-28T14:58:33Z")
2008/8/28 Avinash M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): > something like this(in perl) > sub get\_random\_val\_generator { > my $arr = shift; > return sub { return $arr-\>[rand @$arr] }; > } You can do array = … rand\_gen = lambda { array[rand(array.size)] } … item = rand\_gen[] # or item = rand\_gen.call > 1. How to store these references(subrefs) in a hash or some variable? hash[some\_key] = some\_object # everything is an object > 1. How would you do(approach) this in Ruby(the script)? My Perl is a bit rusty and, frankly, I’m not inclined to spent the efforts to analyze it. Can you describe it? Cheers robert ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [August 28, 2008, 10:40pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/5 "2008-08-28T22:40:46Z")
Avinash M. wrote: > Can somebody please me tell the way to write this script in Ruby? just do this - no-one will ever know 😉 system “perl #{ARGV[0]}” ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [August 28, 2008, 10:20pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/6 "2008-08-28T22:20:44Z")
On Thu, Aug 28, 2008 at 2:51 PM, Robert K. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)wrote: > > in Ruby) > > … > > efforts to analyze it. Can you describe it? > > Unless I’m mistaken, the gist of it is: Take a bunch of templates: adm has _QTY_ _CAR_ cars ssn has _QTY_ _CAR_ cars In an infinite loop, pick one randomly, and replace the _QTY_ and _CAR_ placeholders by values taken from the ‘vals’ fields in the following hash: my %value\_map = ( ‘_CAR_’ =\> { ‘order’ =\> ‘rand’, ‘vals’ =\> [qw(bentley merc bmw audi porsche ford honda lexus)] }, ‘_QTY_’ =\> { ‘order’ =\> ‘rand’, ‘vals’ =\> [1…10] } ); The way values are chosen depends on the ‘order’ field, which can be either random (‘rand’) or sequential (‘seq’). In ruby, you could replace the value\_map by using a more class-oriented approach: RandomMessageValue.new(:qty, (1…10).to\_a) RandomMessageValue.new(:car, %w(bentley merc bmw audi porsche ford honda lexus) And you have SeqMessageValue if you want something sequential. Both RandomMessageValue and SeqMessageValue inherit from MessageValue. A MessageValue object knows how to choose the next value in the array of values (with different implementations). Then you just need a Message class, which has a list of templates, and a list of MessageValue objects. Message knows how to replace the content of a MessageValue inside a template. Voilà . Cheers, Emm ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [September 3, 2008, 6:25am UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/7 "2008-09-03T06:25:51Z")
On Aug 28, 7:23 am, Avinash M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > ``` > 'adm has _QTY_ _CAR_ cars', > 'order' => 'rand', > my ($nval) = $v->{gen}->(); > my $last = 0; > return sub { return $arr->[rand @$arr] }; > die "Invalid value order in value_map\n"; > > ``` > > } > > 1; > > ;-------------------------------------------------- message\_templates = ‘adm has _QTY_ _CAR_ cars’, ‘ssn had _QTY_ _CAR_ cars’ get\_rand = proc{|a| a[rand( a.size )] } $last = -1 get\_seq = proc{|a| $last = $last.next % a.size; a[$last] } value\_map = { ‘_CAR_’ =\> [ get\_seq, %w(bentley merc bmw audi porsche ford honda lexus) ], ‘_QTY_’ =\> [get\_rand, (1…10).to\_a] } while true do puts get\_rand[message\_templates].gsub( /_.\*?_/ ){|s| prc, list = value\_map[s] prc[list] } end — output — ssn had 1 honda cars ssn had 10 lexus cars adm has 2 bentley cars adm has 6 merc cars adm has 4 bmw cars adm has 4 audi cars ssn had 7 porsche cars adm has 3 ford cars ssn had 5 honda cars adm has 10 lexus cars ssn had 7 bentley cars adm has 6 merc cars … ---
**Author:** ![avinash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/ed655f/32.png) [@avinash](https://www.ruby-forum.com/u/avinash)\ **Post date:** [September 4, 2008, 4:15pm UTC](https://www.ruby-forum.com/t/how-would-this-perl-script-look-in-ruby/147109/8 "2008-09-04T16:15:58Z")
On Sep 2, 11:20 pm, William J. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > use Data::Dumper; > > ‘order’ =\> ‘rand’, > > my ($next\_msg, $val\_map) = @\_; > > > > # return $arrya[$last + 1] elem of array; $last is remembered across > > > ``` > > $v->{gen} = get_seq_val_generator($v->{vals}); > > > > ``` > > message\_templates = > ‘_QTY_’ =\> [get\_rand, (1…10).to\_a] > ssn had 1 honda cars > adm has 6 merc cars > … message\_templates = ‘adm has _QTY_ _CAR_ cars’, ‘ssn had _QTY_ _CAR_ cars’ get\_rand = proc{|a| a[rand( a.size )] } get\_seq = proc{|a| a.last[a[0] = a[0].next % a.last.size ] } value\_map = { ‘_CAR_’ =\> [ get\_seq, [ -1, %w(bentley merc bmw audi porsche ford honda lexus) ] ], ‘_QTY_’ =\> [get\_rand, (1…10).to\_a] } while true do puts get\_rand[message\_templates].gsub( /_.\*?_/ ){|s| prc, list = value\_map[s] prc[list] } end