From: Josselin <josselin@...>
Date: 2006-08-11T15:50:05+09:00
Subject: Re: good writing in Ruby...

On 2006-08-10 18:25:19 +0200, Philip Hallstrom <ruby@philip.pjkh.com> said:

>> I know I can write it the 'ugly common way' (loop)
>> but I'd like to see how it can be done the Ruby way ... (I am a newbie...)
>> 
>> here is an array
>> roles = [ "a", "b", "c", "d", "e" ]
>> 
>> Depending upon a variable 'user.role',
>> I would like to  suppress all elements in the array , less or equal to 
>> this variable
>> 
>> ex :
>> user.role = "a"    #=> roles = ["b", "c", "d", "e" ]    		"a" deleted
>> user.role = "b"    #=> roles = ["c", "d", "e" ]   		"a", "b" deleted
>> user.role = "c"    #=> roles = [ "d", "e" ]   			"a", "b", "c" deleted
>> user.role = "d"    #=> roles = [ "e" ]    				"a", "b", "c", "d"  deleted
>> user.role = "e"    #  do nothing
> 
> Maybe...
> 
> roles = roles.map {|x| x <= user.role ? x : nil }.compact
> 
> haven't tested it though...

I'll test it, values in array are strings  :  'god', 'administrator', 
''manager', 'owner', 'customer'
exclusion is based on a prority order
if current_user role is 'god' then exclude 'god'  (there can be only one god)
if current_user role is 'administrator' then exclude 'god'  and 'administrator'
if current_user role is 'manager' then exclude 'god'  and 
'administrator' and 'manager'
if current_user role is 'owner' then exclude 'god'  and 'administrator' 
and 'manager' and 'owner'
...
as roles could change in the future (and also ro avoid possible 
localization issues) I believe it would be better to work with an 
additional integer priority field in the 'role' table, so I can sort 
the collection on priority and get a sorted roles array whatever is in 
the table...
thanks