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From: Uwe Klein on 20 Apr 2010 12:41
Donald G Porter wrote:
> Uwe Klein wrote:
>
>> I am too dumb to compare strings.
>> But I can sort them:
>
>
> Why not use [lsort -dictionary] if the aim is sorting?

duh!

uwe
From: Glenn Jackman on 20 Apr 2010 15:17
At 2010-04-20 12:20PM, "Donald G Porter" wrote:
> Uwe Klein wrote:
> > I am too dumb to compare strings.
> > But I can sort them:
>
> Why not use [lsort -dictionary] if the aim is sorting?
>
> The [lsort -dictionary] command could also be the core of
> a pairwise comparison function, but I'll leave it to other
> to test whether the performance of such a thing is acceptable
> and/or better than other alternatives.

Here's an implementation

proc string_comp_dictionary {s1 s2} {
if {$s1 eq $s2} {
return 0
} else {
set l [list $s1 $s2]
if {$l == [lsort -dictionary $l]} {
return -1
} else {
return 1
}
}
}

Is that the best way to examine list equality? I also considered
examining them as strings:

{"$s1 $s2" eq [join [lsort -dictionary [list $s1 $s2]]]}

--
Glenn Jackman
Write a wise saying and your name will live forever. -- Anonymous
From: Donald G Porter on 20 Apr 2010 17:13

>> The [lsort -dictionary] command could also be the core of
>> a pairwise comparison function, but I'll leave it to other
>> to test whether the performance of such a thing is acceptable
>> and/or better than other alternatives.

Georgios Petasis wrote:
> In my opinion this shows that string compare is missing an option. Isn't
> it?

I think a good case could be made that the comparison function embedded
in [lsort -dictionary] ought to be exposed to scripts as an independent
command.

I do not think it would be a good idea to do so by adding an option to
[string compare]. As a matter of taste, I don't much like options. If
a command doesn't do what you want, create a new one that does, rather
than add an option to transform an existing command into a different one.

What about "-nocase" you ask? I lost.

DGP
From: Rohit M on 21 Apr 2010 00:19
On Apr 20, 9:07 pm, Donald G Porter <d...(a)nist.gov> wrote:
> Rohit M wrote:
> >         if { [expr {$numeralVal1} ] > [expr {$numeralVal2}] } {
>
> Please find whoever taught you that and tell them never to teach
> Tcl again.
>
> DGP

I have not one to blame DGP, self taught. But I know the code is
wrong,
written hurriedly, dont think there is need to do expr as we already
have pure numbers.
From: Rohit M on 21 Apr 2010 00:20
On Apr 21, 12:17 am, Glenn Jackman <gle...(a)ncf.ca> wrote:
> At 2010-04-20 12:20PM, "Donald G Porter" wrote:
>
> >  Uwe Klein wrote:
> > > I am too dumb to compare strings.
> > > But I can sort them:
>
> >  Why not use [lsort -dictionary] if the aim is sorting?
>
> >  The [lsort -dictionary] command could also be the core of
> >  a pairwise comparison function, but I'll leave it to other
> >  to test whether the performance of such a thing is acceptable
> >  and/or better than other alternatives.
>
> Here's an implementation
>
>     proc string_comp_dictionary {s1 s2} {
>         if {$s1 eq $s2} {
>             return 0
>         } else {
>             set l [list $s1 $s2]
>             if {$l == [lsort -dictionary $l]} {
>                 return -1
>             } else {
>                 return 1
>             }
>         }
>     }
>
> Is that the best way to examine list equality?  I also considered
> examining them as strings:
>
>     {"$s1 $s2" eq [join [lsort -dictionary [list $s1 $s2]]]}
>
> --
> Glenn Jackman
>     Write a wise saying and your name will live forever. -- Anonymous

Thanks Glenn, I think this would be faster that what I have.
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