Are there some features like zip and fold in Perl?

Question

I want to use some function like "zip" , "fold" and "map" in perl. (Like in Haskell.) I found a map, and it works well. Then, zipper and crease? Thank you very much.

Answer 1

In my List :: Gen module, I implemented many of these functions (and even Haskell-like lazy ones)

use List::Gen qw(zip reduce); my @list = zip [1 .. 4], ['a' .. 'd']; my $str = reduce {$a . $b} @list; say $str; # 1a2b3c4d 

Or using the glob function to build ranges:

 use List::Gen 'glob'; say <1 .. 4>->zip(<a .. d>)->reduce('$a.$b'); # 1a2b3c4d 

Using ->reduce('.') Or ->reduce(sub {$a . $b}) also works.

Or if you play golf:

 say <[.]>->(<1..4>|<a..d>); 

Or for Haskell versions, see List :: Gen :: Haskell

Answer 2

The List::Util library has reduce() , which does what fold does.

List::MoreUtils contains the zip() function.

Not built-in, mainly because Perl is not a functional programming language.

Answer 3

If you are interested in using functional programming concepts in Perl, I highly recommend that you read the higher order of Perl .

Answer 4

Modules that provide functional programming tools:

• Perl map and grep
• List :: Util
• List :: MoreUtils
• List :: Gen and List :: Gen :: Haskell (including lazy lists)
• Algorithm :: Loops

You may also be interested in a book (now free to download) Higher Perl order .