Get ranges from a list of numbers (like 1,2,3 => 1-3)

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

Hello dear Monks. Say, I have a sorted list like this: 1,2,3,4,9,16,22,23,24,30,35 I want to transform it to: 1-4,9,16,22-24,30,35 So that ranges of numbers are spelled as ranges, not as lists. I know how to solve the inverse problem:

use Set::IntSpan;
my $span = Set::IntSpan->new('1-4,9,16,22-24,30,35');
print join "," => $span->elements();
[download]

would give me 1,2,3,4,9,16,22,23,24,30,35 . Is there a way to make ranges from a list? Maybe, modules similar to Set::IntSpan, or some algorithm?.. Thanks in advance.

Comment on Get ranges from a list of numbers (like 1,2,3 => 1-3) Select or Download Code

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Re: Get ranges from a list of numbers (like 1,2,3 => 1-3) by aitap (Curate) on Apr 09, 2013 at 16:46 UTC
Well, searching "range from list" reveals the thread: [Solved] Converting a list of numbers to use a range operator, which suggests using Set::IntSpan's `run_list` method: `my @array = (2,3,4,10,11,12); my $set = new Set::IntSpan join(',', @array); my $list = $set->run_list; # $list is now "2-4,10-12"` [download]	[reply] [d/l] [select]
Re^2: Get ranges from a list of numbers (like 1,2,3 => 1-3) by Doctrin (Beadle) on Apr 09, 2013 at 19:04 UTC
Thank you! That is exactly what I need!	[reply]
Re: Get ranges from a list of numbers (like 1,2,3 => 1-3) by SuicideJunkie (Vicar) on Apr 09, 2013 at 16:52 UTC
Quoth the CPAN: print $set->as_string(), "\n"; # prints 1,3,5,7,9,100-1000000 It sounds like Set:IntSpan already does what you want. Just keep reading down the page a little further to Getting Set Contents	[reply]
Re: Get ranges from a list of numbers (like 1,2,3 => 1-3) by LanX (Saint) on Apr 09, 2013 at 16:45 UTC
Same question again in such short interval? Smells like homework spirit. Cheers Rolf ( addicted to the Perl Programming Language)	[reply]
Re^2: Get ranges from a list of numbers (like 1,2,3 => 1-3) by Doctrin (Beadle) on Apr 09, 2013 at 19:03 UTC
Haha, no, that is coincidence... It looks like I should use perlmonks' local search engine... I just googled "perl module to make a range from a list site:perlmonks.org" and did not find that question :( Maybe, searchphrase was not so good. Anyways, thank you very much!	[reply]
Re^2: Get ranges from a list of numbers (like 1,2,3 => 1-3) by grizzley (Chaplain) on Apr 11, 2013 at 06:37 UTC
Or like golfing problem.	[reply]
Re: Get ranges from a list of numbers (like 1,2,3 => 1-3) by daxim (Curate) on Apr 09, 2013 at 16:47 UTC
Call the method run_list, or use the object in string context.	[reply]