in reply to Re: Moose log string class
in thread Moose log string class

Regarding:

a) Thanks.

b) I did not understand what you said.

c) I found nothing in the cookbook about explicit "reader" and "writer" attribute modifiers as described in the Moose Manual about Attributes

For example, I'd like to do something like this (which does not work with Moose even though one is supposed to be able to explicitly specify "reader" and "writer" accessors by name): 
package QuackLog; use Moose; use namespace::autoclean; use strict; my 
+@log_string_parts = qw(timestamp foo bar baz qux norf quack honk woof
+ meow blerf); has $_=> (is => 'rw') for(@log_string_parts); has log_s
+tring => ( is => 'rw', reader=> 'get_log_string', writer => 'set_log_
+string', ); sub get_log_string{ my ($self) = shift; return(join ' ',m
+ap {$self->can($_);$self->$_} @log_string_parts); } sub set_log_strin
+g{ my ($self,$s)=@_; my @part_values=split / /,$s; for my $method (@l
+og_string_parts){ $self->can($method); $self->$method(shift @part_val
+ues); } $self; } __PACKAGE__->meta->make_immutable();

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This, however, produces a compile time error:

You are overwriting a locally defined method (get_log_string) with an 
+accessor...

[download]

PS: I did try the symbolic $method lookup, having used it many times before in Perl objects, but for some reason it didn't work, and I attributed the failure to my lack of understanding of Moose rather than the more likely explanation which was just a bad choice of syntax.

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Re^3: Moose log string class ( cached attribute trigger clearer )
by Anonymous Monk on Feb 12, 2015 at 03:38 UTC

    b) word explanation of problem, question, ahead of "color b) I did not understand what you said.

    Instead of "humbleness" like "Being a mere calf...", use more words to explain the conext/programming problem

    Instead of having us guess what you think get_log_string and set_log_string are supposed to do, explain what they're supposed to do

    When you were talking about a reader/writer, it wasn't clear you were talking about Moose has() options , see below

    Also, you only show a class declaration, but no use case

    For example, I'd like to do something like this (which does not work with Moose even though one is supposed to be able to explicitly specify "reader" and "writer" accessors by name): You are overwriting a locally defined method (get_log_string) with an accessor...

    Did you know has() creates subroutines? So that you can write the following without writing a sub reader ... and sub write ...? 

    my $val = $obj->reader;
$obj->write( $newval);

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    So, if has() is creating subroutines (getter/setter), to change some attribute ...

    what are your get_log_string and set_long_string supposed to do?

    Are you supposed to have a "has log_string"?

    This brings up check the cookbook again... there is stuff in there

    So i come up with

    Read more... (3 kB)

    So when an attribute is updated the log_string isn't, so back to cookbook

    Read more... (3 kB)

    Does this do what you want? Maybe

    Is it a good idea , good OOP/OOD? Maybe

    Does Moose teach you good OOP/OOD? No :)

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