NAME HATX - A fluent interface for Hash and Array Transformations SYNOPSIS use HATX qw/hatx/; # Multiple versions of journal.html and projmgmt.html my $files = [ 'journal-v1.0.tar.gz 1201', 'journal-v1.1.tar.gz 1999', 'journal-v1.2.tar.gz 3100', 'projmgmt-v0.1.tar.gz 250', 'projmgmt-v0.2.tar.gz 350' ]; # Declare a helper object my $max = { journal => '0.0', projmgmt => '0.0' }; # hatx($obj) clones $obj; no clobbering my $h = hatx($files) # Internal object becomes equivalent to: # [ 'journal-v1.0.tar.gz 1201', # 'journal-v1.1.tar.gz 1999', # 'journal-v1.2.tar.gz 3100', # 'projmgmt-v0.1.tar.gz 250', # 'projmgmt-v0.2.tar.gz 350' ] # Extract components: file, version, bytes ->map(sub { $_[0] =~ /(journal|projmgmt)-v(.+).tar.gz\s+(\d+)/; return [$1, $2, $3]; # e.g. ['journal', '1.0', 1201] }) # Internal object becomes equivalent to: # [ ['journal', '1.0', 1201] # ['journal', '1.1', 1999] # ['journal', '1.2', 3100] # ['projmgmt', '0.1', 250] # ['projmgmt', '0.2', 350] ] # Accumulate file count and file sizes ->apply(sub { my ($v, $res) = @_; $res->{count}++; $res->{bytes} += $v->[2]; }, my $stats = { count => 0, bytes => 0 }) # Internal object unchanged # The $stats variable becomes { count => 5, bytes => 6900 } # Determine the max version of each file, store into $max ->apply(sub { my ($v, $res) = @_; my ($file, $ver, $size) = @$v; if ($ver gt $res->{$file}) { $res->{$file} = $ver } }, $max) # Internal object unchanged # $max variable becomes { journal => '1.2', projmgmt => '0.2' } # Keep only the max version ->grep(sub { my ($v, $res) = @_; my ($file, $ver, $size) = @$v; return $ver eq $res->{$file}; }, $max) # Internal object reduced to: # [ ['journal', '1.2', 3100] # ['projmgmt', '0.2', 350] ] ; METHODS map Apply the given function to each item in the href/aref. The given function has the following signature: fn($k,$v) -> ($k,$v) # Applied to href fn($v) -> ($v) # Applied to aref The internal href/aref IS modified. grep Apply the given function to each item in the href/aref. The given function has the following signature: fn->($k,$v[,@args]) -> BOOLEAN # Applied to hashref fn->($v[,@args]) -> BOOLEAN # Applied to arrayref WHERE fn A function reference that returns a boolean value $k,$v The key-value pair of a hash $v An item of an array @args An optional list of user variables Items where the fn returns a True value are kept. sort( $fn ) DESCRIPTION Sorts contents of arrayref. Hashrefs are unmodified. ARGUMENTS $fn - A function reference with prototype ($$). See https://perldoc.perl.org/functions/sort. EXAMPLES # Sort descending alphabetically hatx($aref)->sort(sub ($$) { $_[1] cmp $_[0] }); # Sort ascending numerically hatx($aref)->sort(sub ($$) { $_[0] <=> $_[1] }); # Sort descending numerically hatx($aref)->sort(sub ($$) { $_[1] <=> $_[0] }); to_href Convert internal aref to href using the given function. $fn->($val) -> ($key, $val) $fn is a FUNCTIONREF that takes a single value and returns two values to_aref( $fn [,@args] ) DESCRIPTION Convert internal hashref to an arrayref. ARGUMENTS $fn - A user-provided function reference with signature: $fn->($hkey, $hval [,@args]) return ($val) WHERE $hkey Key of source hashref pair $hval Value of source hashref pair @args Optional user variables $val An element of the target arrayref @args - Optional arguments that are passed through to $fn apply Apply the given function to each item in the href/aref. Arguments can be provided to store results of the function application e.g. finding the max value. The internal href/aref is not modified. fn($k,$v,@args) -> () fn($v,@args) -> () AUTHOR Hoe Kit CHEW COPYRIGHT Copyright 2024- Hoe Kit CHEW LICENSE This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. SEE ALSO