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From: yahalom on 4 Jul 2008 06:11
I was playing with the new "in" and "ni" new expression operators and
found that I cannot do:

if {$test in [list 3 4 5] || $test ni [list 5 6 7]} {
puts "great!"
}

Are the new expression operators"ni" and "in" limited to one operator?
why?

I checked the doc http://www.tcl.tk/man/tcl8.5/TclCmd/if.htm and did
not see any mention of the new expression operators. where are they
documented?
From: schlenk on 4 Jul 2008 06:27
On Jul 4, 12:11 pm, yahalom <yahal...(a)gmail.com> wrote:
> I was playing with the new "in" and "ni" new expression operators and
> found that I cannot do:
>
> if {$test in [list 3 4 5] || $test ni [list 5 6 7]} {
> puts "great!"
>
> }
>
> Are the new expression operators"ni" and "in" limited to one operator?
> why?
>
> I checked the dochttp://www.tcl.tk/man/tcl8.5/TclCmd/if.htmand did
> not see any mention of the new expression operators. where are they
> documented?

AS Tcl 8.5.2
(bin) 4 % set test 3
3
(bin) 5 % if {$test in [list 4 5 6] || $test ni [list 7 8 9]} {
> puts "Great"
> }
Great

why do you assume it does not work?

The operators are documented on the expr manpages.

Michael
From: Glenn Jackman on 4 Jul 2008 09:33
At 2008-07-04 06:11AM, "yahalom" wrote:
> I was playing with the new "in" and "ni" new expression operators and
> found that I cannot do:
>
> if {$test in [list 3 4 5] || $test ni [list 5 6 7]} {
> puts "great!"
> }

What about this can't you do? What do you see and how does that differ
from your expectations?

% for {set test 2} {$test < 9} {incr test} {
puts $test
if {$test in [list 3 4 5] || $test ni [list 5 6 7]} {puts Great}
{puts Terrible}
}
2
Great
3
Great
4
Great
5
Great
6
Terrible
7
Terrible
8
Great

> I checked the doc http://www.tcl.tk/man/tcl8.5/TclCmd/if.htm and did
> not see any mention of the new expression operators. where are they
> documented?

Some control commands ([if], [while], [for] come to mind) send their
(often first) argument to [expr]. You would have read this in the if
man page:

SYNOPSIS

if expr1 ?then? body1 elseif expr2 ?then? body2 elseif ... ?else? ?bodyN?

DESCRIPTION

The if command evaluates expr1 as an expression (in the same way
that expr[linked to expr man page] evaluates its argument).

--
Glenn Jackman
Write a wise saying and your name will live forever. -- Anonymous
From: Glenn Jackman on 4 Jul 2008 09:35
At 2008-07-04 06:11AM, "yahalom" wrote:
> I was playing with the new "in" and "ni" new expression operators and
> found that I cannot do:
>
> if {$test in [list 3 4 5] || $test ni [list 5 6 7]} {
> puts "great!"
> }

What about this can't you do? What do you see and how does that differ
from your expectations?

% for {set test 2} {$test < 9} {incr test} {
puts $test
if {$test in [list 3 4 5] || $test ni [list 5 6 7]} {
puts Great
} else {
puts Terrible
}
}
2
Great
3
Great
4
Great
5
Great
6
Terrible
7
Terrible
8
Great

> I checked the doc http://www.tcl.tk/man/tcl8.5/TclCmd/if.htm and did
> not see any mention of the new expression operators. where are they
> documented?

Some control commands ([if], [while], [for] come to mind) send their
(often first) argument to [expr]. You would have read this in the if
man page:

SYNOPSIS

if expr1 ?then? body1 elseif expr2 ?then? body2 elseif ... ?else? ?bodyN?

DESCRIPTION

The if command evaluates expr1 as an expression (in the same way
that expr[linked to expr man page] evaluates its argument).

--
Glenn Jackman
Write a wise saying and your name will live forever. -- Anonymous
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