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variable declaration only

Posted by neo (The Architect), 2 May 2005
How do I just declare a variable in TCL?
or at least how do I weed out null "{}" entries from a list?
I needed to create a list so I did an
Code:
lappend $var;

but this gives it a null entry i think. Is there any other way tp do this. I can't do a
Code:
list..
in the for loop as i don't know when i will enter that part of the loop.


Posted by admin (Graham Ellis), 2 May 2005
All variables in Tcl contain strings (slight exception - arrays contain one or more strings).  If you want to remove empty strings from a list, try something like

Code:
#/usr/bin/tclsh

set wotsit [list tom "" dick "" "" harry ""]
puts $wotsit

while {[set where [lsearch -exact $wotsit ""]] > -1} {
       set wotsit [lreplace $wotsit $where $where]
       }

puts $wotsit


Testing ....

earth-wind-and-fire:~/may05 grahamellis$ tclsh wi
tom {} dick {} {} harry {}
tom dick harry
earth-wind-and-fire:~/may05 grahamellis$


Yes, that works

Posted by neo (The Architect), 3 May 2005
Thanks a lot for that. It works now.
I have another query though. I've posted it here http://www.wellho.net/cgi-bin/opentalk/YaBB.pl?board=tcl;action=display;num=1115113410



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