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Re: I need hash inside a hash help

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From:
JJ Merelo
Date:
January 11, 2019 19:33
Subject:
Re: I need hash inside a hash help
Message ID:
CAJoLtgejrwTpWcO+9rUAnPJgz3DmTXn4jQmqDGQ94=HSvZwcUQ@mail.gmail.com
I think you want $x, not $Ace.

Cheers

El vie., 11 ene. 2019 a las 20:26, ToddAndMargo via perl6-users (<
perl6-users@perl.org>) escribió:

> On 1/11/19 11:16 AM, Bruce Gray wrote:
> >
> >
> >> On Jan 11, 2019, at 12:41 PM, ToddAndMargo via perl6-users <
> perl6-users@perl.org> wrote:
> >>
> >> Hi All,
> >>
> >> How do I do a hash inside a hash?
> >>
> >> So far I have:
> >>
> >> $ p6 'my %Vendors=("acme" => ( "ContactName" => "Larry, "AccountNo" =>
> 1234 ) ); say %Vendors;'
> >> ===SORRY!=== Error while compiling -e
> >>
> >>
> >> I want to be able to have both a Contact Name and and AccountNo
> >> associated with each key in %Vendors.
> >>
> >>
> >> Many thanks,
> >> -T
> >
> > First, you need a double-quote after `Larry` (before the comma) to fix
> the syntax error:
> >       perl6 -e 'my %Vendors=("acme" => ( "ContactName" => "Larry",
> "AccountNo" => 1234 ) ); say %Vendors;'
> >
> > At this point, you have a Hash of List of Pairs. To change it into a
> Hash of Hashes, change the inner parens to curly braces:
> >       perl6 -e 'my %Vendors=("acme" => { "ContactName" => "Larry",
> "AccountNo" => 1234 } ); say %Vendors; say %Vendors<acme><AccountNo>;'
> >
> > Those inner parens were acting as an anonymous list constructor, but you
> needed an anonymous *hash* constructor, which is what the curly braces do
> (when they are not doing their code-block-ish job).
> >
> > You could have also used `Hash(…)` or `%(…)` instead of `{…}`, but `{…}
> is shortest, and most traditional from Perl 5.
> >
> > —
> > Hope this helps,
> > Bruce Gray (Util of PerlMonks)
> >
>
> Hi Bruce,
>
> Thank you!
>
> This works,
>
> $ p6 'my $x="Ace"; my %Vendors=("acme" => { "ContactName" => "Larry",
> "AccountNo" => 1234 }, "Ace" => { "ContactName" => "Mo", "AccountNo" =>
> "A102" } ); say "%Vendors<Ace><ContactName>" ~ "\t" ~
> "%Vendors<Ace><AccountNo>";'
> Mo      A102
>
>
> but I have to access it by a variable.  "Now" what am I doing wrong?
>
> $ p6 'my $x="Ace"; my %Vendors=("acme" => { "ContactName" => "Larry",
> "AccountNo" => 1234 }, "Ace" => { "ContactName" => "Mo", "AccountNo" =>
> "A102" } ); say "%Vendors<$Ace><ContactName>" ~ "\t" ~
> "%Vendors<$Ace><AccountNo>";'
> Use of uninitialized value of type Any in string context.
>
>
> Many thanks,
> -T
>


-- 
JJ

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