my @all_names = map { {name => $_->{name}} } @{ $data }[1 .. $#$data];
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This line works, but


my @all_names = map { {name => $_->{name}} } @{ $data }[1 .. $#$data];
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I just need some explaining in how different one line of code is from another, why wouldn't the name=>"Accounts" be picked up by the code here:


use warnings;
use strict;
use Data::Dumper;

my $data = 
[
  {
    val => "action",
    name => "Accounts",
    id => "None",
  },
  { name => "PA1", id => "AUTOB" },
  { name => "PB3", id => "AUTOP" },
  { name => "BOX", id => "BOP" },
  { name => "DW0", id => "DFIRE" },
  { name => "QW3", id => "HOME" },
  { name => "CM7", id => "CUMBR" },
  { name => "BR1", id => "PUMBR" },
  { name => "TY6", id => "ECUST" },
]
;

#my @all_names = map { $_->{name} } @{ $data }[1 .. $#$data];
#my @hash_names = map{ {name=>$_} } $data;
my @all_names = map { {name => $_->{name}} } @{ $data }[1 .. $#$data];

print Dumper(\@all_names);
#print Dumper \@hash_names;

__END__
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Such a good answers , thanks!

why wouldn't the name=>"Accounts" be picked up

Because you start at element #1, not 0:

[1 .. $#$data];
 ^
 |
 |
 Here!
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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why wouldn't the name=>"Accounts" be picked up

In your original data the first element of the array is unwanted so toolic has @{ $data }[1 .. $#$data] which has the effect of skipping that first element. Arrays are indexed from "0" so the first element is $array[0], the second element is $array[1] and so on. So, @{ $data }[1 .. $#$data] means the range of elements starting at the second element and up to the last element.

A better way might be to use grep in combination with map:

my @all_names =
    map { {name => $_->{name}} }
    grep { exists $_->{name} }
    @$data;
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Here grep first filters all the elements, discarding any which don't have a 'name' key, and then map constructs the desired data structure from the remaining elements.

The point to map is that you can run the elements of the list through any code you like in the map block.

map assigns the result of the last evaluated statement in the block, you don't always have to can't say return $foo;, but can just say $foo, as shown in all these examples. I tend to eschew many of Perl's shortcuts (like omitting a return statement from a block) because I prefer readability, but when it's a single statement, as is often the case with map, it's nice to be able to skip it.

my @hash_names = map{ return {name => $_}; } @all_names;
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Using return in a map returns from the enclosing subroutine. Cf:

say for sub { map { "\U$_" } @_ } ->(qw( abc def ghi ));
# ABC
# DEF
# GHI
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versus

say for sub { map { return "\U$_" } @_ } ->(qw( abc def ghi ));
# ABC
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and even

say for map { return "\U$_" } qw( abc def ghi );
# Can't return outside a subroutine at -e line 1.
# [255]
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
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