Re: Parsing namespace name strings

On 29/11/2024 23:16, Emiliano wrote:

On Fri, 29 Nov 2024 21:03:25 +0000
Alan Grunwald <nospam.nurdglaw@gmail.com> wrote:
 

I find I regularly want to know things like "what is first part of a
namespace name", "the first two parts" etc. I generally want to get the
same answer whether the name is a::b::c or ::a::b::c.
>
I can (and do) do this by getting a list of parts via something like
>
split [string map {"::" ":"} $name] ":"
>
but this is clunky - is there something like [namespace split] that
would return a list of parts?
>
For example, I'd like namespace split a::b::c to return {a b c}, and
namespace split ::d::e::f::g to return {d e f g}.

 Easy combining [namespace tail] and [namespace qualifiers]:
 proc ns2list {ns} {
   set l {}
   while {$ns ne {}} {
     lappend l [namespace tail $ns]
     set ns [namespace qualifiers $ns]
   }
   lreverse $l
}
 % ns2list foo::bar::
foo bar {}
% ns2list foo::bar
foo bar
% ns2list ::::foo::bar::
foo bar {}
% ns2list ::foo::bar
foo bar
% ns2list {}
%
 

>
As a followup, if I write a proc namespaceSplit that does what I want,
is there a user-level way to modify the [namespace] command so that a
can execute namespaceSplit via [namespace split]?

 Since the [namespace] command is an ensemble, its easy to add a subcommand
 % namespace ensemble configure namespace -map [dict merge [namespace ensemble configure namespace -map] {split ::ns2list}]
% namespace split ::foo::bar::baz
foo bar baz
 

>
Many thanks

 Regards

Thanks Emiliano.
I did some testing after I posted last night, and I found that manipulating the name with [string] commands ran faster than with [namespace tail] and [namespace qualifiers]. I must admit that when using the [namespace] subcommands, I was processing the list with [linsert l 0 ...] rather than using [lappend l] and [lreverse] which probably makes a difference.
Thanks also for the pointer about adding a new subcommand to the namespace ensemble. I've never played with [namespace ensemble] before and I can see why I was a little intimidated.
--
Alan