Re^2: Sorting Template Toolkit Array of Hashrefs

[roho]

The TT documentation says ...

"When an item in the list is a hash reference, the search key will be used to retrieve a value from the hash which will then be used as the comparison value".

Since row.agendas.0.agendaDate retrieves the value inside the FOREACH loop, it seems reasonable that it would retrieve the value for the sort comparison, but alas it's not doing that. :(

[Anonymous Monk]

Since row.agendas.0.agendaDate retrieves the value inside the FOREACH loop,

But that is not a (singular) key or method , it is a compound expression

Template::Manual::VMethods says

An argument can be provided to specify a search key. Where an item in the list is a hash reference, the search key will be used to retrieve a value from the hash which will then be used as the comparison value. Where an item is an object which implements a method of that name, the method will be called to return a comparison value.

To see how its implemented view sub Template::VMethods::list_sort

[roho]

So that begs the question ... how to turn the compound expression into a singular key?

[Anonymous Monk]

So that begs the question ... how to turn the compound expression into a singular key?

Don't :)

If you view the source, you can see the current implementation

If you're smart enough you could alter it to accept  [ agendas', 0, 'agendaDate' ] to sort by agendas.0.agendaDate

If you're really smart, you'll do any such sorting/prep required from within perl and simplify the data structure you give the template ( adjust your "model" )

[Anonymous Monk]

This is how I explored before source diving in Sorting Template Toolkit Array of Hashrefs

[%#
## tpage                     sort.compound.tt
## tpage --debug=2047        sort.compound.tt
## tpage --debug=all         sort.compound.tt
## 
## tpage --debug=off         sort.compound.tt
## tpage --debug=vars        sort.compound.tt
## tpage --debug=filters     sort.compound.tt
## tpage --debug=dirs        sort.compound.tt
## tpage --debug=provider    sort.compound.tt
## tpage --debug=plugins     sort.compound.tt
#~ unknown debug flag ## tpage --debug=flags       sort.compound.tt
## tpage --debug=stash       sort.compound.tt
## tpage --debug=undef       sort.compound.tt
## tpage --debug=context     sort.compound.tt
## tpage --debug=caller      sort.compound.tt
## tpage --debug=parser      sort.compound.tt
## tpage --debug=all         sort.compound.tt
## tpage --debug=on          sort.compound.tt
## tpage --debug=service     sort.compound.tt
## 
## http://perlmonks.org/?node_id=982470# Re^3: Sorting Template Toolki
+t Array of Hashrefs
## 
## 
## 
## COMMENTS END
-%]
[% 
   SET results = [
        { 'a' => [ { 'b' => 6 } ] },
        { 'a' => [ { 'b' => 3 } ] },
        { 'a' => [ { 'b' => 4 } ] },
        { 'a' => [ { 'b' => 9 } ] },
   ];
%]


[% USE Dumper Indent = 0;
   GET Dumper.dump( results );
%]
##
[% FOREACH item IN results.sort %]
[% USE Dumper Indent = 0; GET Dumper.dump( item ); -%]
[% END %]
##
[% FOREACH item IN results.nsort('a.0.b') %]
[% USE Dumper Indent = 0; GET Dumper.dump( item ); -%]
[% END %]

####################
####################
[% 
   SET results = [
        { 'a' => [ { 'b' => 6 } ], 'a.0.b' => 6 },
        { 'a' => [ { 'b' => 3 } ], 'a.0.b' => 3 },
        { 'a' => [ { 'b' => 4 } ], 'a.0.b' => 4 },
        { 'a' => [ { 'b' => 9 } ], 'a.0.b' => 9 },
   ];

  USE Dumper Indent = 0; 
  FOREACH item IN results.nsort('a.0.b');
    GET Dumper.dump( item );
    GET "\n";
  END;
%]