[Xotcl] nx attribute predefined value constrains, two more possible options?

[Victor Mayevski]

Very nice. It is even better than I thought. ::Slot has been probably the most confusing part of XOTcl for me, hence I only used it for Attribute.

Thanks  


----- Original Message -----
From: "Gustaf Neumann" <neumann at wu-wien.ac.at>
To: "Victor Mayevski" <vitick at gmail.com>
Cc: xotcl at alice.wu-wien.ac.at
Sent: Wednesday, October 27, 2010 12:11:21 AM GMT -08:00 US/Canada Pacific
Subject: Re: nx attribute predefined value constrains, two more possible options?

On 26.10.10 22:58, Victor Mayevski wrote:
> How about adding two move predefined constrains?:
>
> :attribute a:regexp={myregexp}
> :attribute a:glob={myglob}
one can do this with a few lines of code (see below).
In most cases, it is better to name the types (like e.g.
a type isbn), such that the matching pattern/regexp does
not have to be repeated on each usage.

-gustaf neumann

==============================================
::nx::Slot method type=glob {name value pattern} {
   if {![string match $pattern $value]} {
     error "Value '$value' does not match pattern '$pattern'"
   }
}

Class create C {
   :attribute x:glob,arg=*world
   :public method foo {a:glob,arg=*x b:glob,arg=*y} {
     return $a-$b
   }
}

#C create c1 -x abc;             #Error: Value 'abc' does 
not match pattern '*world'
C create c2 -x "hello world"
c2 foo xxx yyy
#c2 foo x aya;         #Error: Value 'aya' does not match 
pattern '*y'