Beefy Boxes and Bandwidth Generously Provided by pair Networks
laziness, impatience, and hubris
 
PerlMonks  

comment on

( [id://3333]=superdoc: print w/replies, xml ) Need Help??

Is there a special variable that tracks what $i is tracking in that example?
Curiously, this is very easy in Python:
x = [ 'apple', 'banana', 'orange' ] for i, val in enumerate(x): print i, val
which prints:
0 apple 1 banana 2 orange
and fairly easy in Ruby:
x = [ 'apple', 'banana', 'orange' ] x.each_with_index { |val, i| print "#{i} #{val}\n" }
and I'm sure (need to wait for moritz to show me how) it's easy in Perl 6 too (probably via Array kv and/or pairs methods?).

I was hoping List::Util or List::MoreUtils might have something nice, but the best I could find is to use an iterator like so:

use List::MoreUtils qw(each_array); my @x = ( 'apple', 'banana', 'orange' ); my $it = each_array( @{[0..$#x]}, @x ); while ( my ($i, $val) = $it->() ) { print "$i $val\n"; }
which is horrific. Is there a better way in List::Util or List::MoreUtils that I missed?

While I was writing this, chromatic showed how to do it in Perl 5.12 or above:

my @x = ( 'apple', 'banana', 'orange' ); while ( my ($i, $val) = each @x ) { print "$i $val\n"; }


In reply to Re^2: Perlplexation - foreach shoulda Known (Rosetta: Perl, Python, Ruby) by eyepopslikeamosquito
in thread Perlplexation - foreach shoulda Known by raybies

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":



  • Are you posting in the right place? Check out Where do I post X? to know for sure.
  • Posts may use any of the Perl Monks Approved HTML tags. Currently these include the following:
    <code> <a> <b> <big> <blockquote> <br /> <dd> <dl> <dt> <em> <font> <h1> <h2> <h3> <h4> <h5> <h6> <hr /> <i> <li> <nbsp> <ol> <p> <small> <strike> <strong> <sub> <sup> <table> <td> <th> <tr> <tt> <u> <ul>
  • Snippets of code should be wrapped in <code> tags not <pre> tags. In fact, <pre> tags should generally be avoided. If they must be used, extreme care should be taken to ensure that their contents do not have long lines (<70 chars), in order to prevent horizontal scrolling (and possible janitor intervention).
  • Want more info? How to link or How to display code and escape characters are good places to start.
Log In?
Username:
Password:

What's my password?
Create A New User
Domain Nodelet?
Chatterbox?
and the web crawler heard nothing...

How do I use this?Last hourOther CB clients
Other Users?
Others chanting in the Monastery: (9)
As of 2024-04-23 14:44 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    No recent polls found