Util

# Trying for a simpler version of https://gist.github.com/gfldex/e28992d7d85451ed669e7942f0b27e30 ,
# because it gets down to the Iterator level, and also evaluates its condition twice for every value.

# All of these versions use the L1 record-matching logic I learned way back in
# the RPG language (where it was built into the language itself as L1,L2...L9 and MR indicators).


# Evaluates its condition N+1 times
sub batch2 (@list, &cluster) {
    return lazy gather {

Util

=begin pod :kind("Language") :subkind("Language") :category("tutorial")

=TITLE Sorting

=SUBTITLE Guide to sorting in Raku

=head1 Quick solutions to common tasks

Simple sorts of list of values:
=begin code

Util

#!env perl6
use v6;

$*ERR.print("Benchmark ", 'Miltiplier', ": ");
my $stime = now;
my $max_l = 20_000;
say :$max_l.perl;
my @l = 1..$max_l; # Hmmm. 2x here increases runtime by 4x
my $n;
for (^100) { # OK 10x here increases runtime by 10x

Util

use v6;

# 2016-02-09  <bruce.gray@acm.org>

my $length = @*ARGS.shift;
say "Length = $length";

my @x = 1..$length;
my @y = @x.reverse;

Util

# I think that this algorithm for handling the gzip'ed output files
# will be more efficient in speed, and vastly better in memory.
use Modern::Perl;

my $divider = 65000;

my ( $fileDate, $fileMinute ) = unpack 'x6 a8 x1 a4', $ARGV[0];


sub format_a_records_file_counter { return sprintf '%02d', $_[0] }

Util

# Just to show off the clarity of Perl 6.
# Code is untested! (Ran out of time.)
my @keys = <
    callingNumber       calledNumber    numberBeforeTranslations dialedNumber
    genericAddressParam ingressProtocol egressProtocol           callDirection
    ingressTgidName     egressTgidName
>;

my @tnFields = @keys[0..4];

Util

# This is what I did to get it Rosella working:
mkdir ~/new_rosella_dir
cd    ~/new_rosella_dir
git clone https://github.com/Whiteknight/Rosella.git
cd Rosella/
# Correct this for your Parrot path
PATH=$PATH:~/Perl/Parrot/Git/Parrot/parrot
# Only needed on Mac OS X
export DYLD_LIBRARY_PATH=~/Perl/Parrot/Git/Parrot/parrot/blib/lib
make

Util

1. Spelling corrected: Schwartzian transform
2. No need to use parens around \d{8}.
3. I like ST better, but GRT is faster for large lists:
    http://www.perlmonks.org/?node_id=145659
4. Need to warn or die to show bad data when regex fails.
5. Perl 6 automatically does ST for you:
    my @sorted = @files.sort({ / SWITCH _ \d**8 _ (\d**6) / or die; $0; });

Util

# Yes, you can put Moose classes in the same source file as your mainline code, rather than doing the CPAN-standard of one class per module.
# However, you must place the class definitions above the uses of the classes.

package Point;
use Moose;

has 'x' => ( isa => 'Int', is => 'rw' );
has 'y' => ( isa => 'Int', is => 'rw' );

__PACKAGE__->meta->make_immutable;

Util

#!perl
use strict;
use warnings;

# This code duplicates "Appendix B The Standard Normal Table"
# from a book used by Alexis in 2012 statistics class.
# 2012-03-09 <bruce.gray@acm.org>
#   Wrote program in Perl 6, then converted to Perl 5.

use constant SQRT_2PI => sqrt( 8 * atan2(1,1) );