Mailinglist Archive: opensuse (2491 mails)

["David C. Rankin" <drankinatty@xxxxxxxxxxxxxxxxxx>]

Guys,

        You need a break from all the 11.2 buzz. Many probably already have 
this, but 
for those that don't, put them in your toolbox. There is nothing new about 
needing to trim whitespace from either the beginning or end of a variable, but 
what is remarkable is the way the following two simple parameter substitutions 
work. (They take staring at for a while)

        The main benefit is there are no wastefull calls to sed (like using a 
sledge 
hammer to swat a fly) and there are no checks required to determine if 
whitespace exists on the front or backend of a string (No more: strln=${#1};  
[[ ${1:$((strlen-1))} == ' ' ]] && ...) and no more loops th count characters. 
Take a look and save them where you can find them again. I ran across them on 
codesnippets.joynet.com:

http://codesnippets.joyent.com/posts/show/1816

VAR="${VAR#"${VAR%%[![:space:]]*}"}"   # remove leading whitespace characters
VAR="${VAR%"${VAR##*[![:space:]]}"}"   # remove trailing whitespace characters

        If you think about it, that is the perfect way to do it. You determine 
the 
exact type and number of leading or trailing whitespace and then you remove 
just those characters (but all in one compact line). I have seen this 
somewhere before, but I wasn't smart enough to save it. Won't happen this time 
:p

-- 
David C. Rankin, J.D.,P.E.
Rankin Law Firm, PLLC
510 Ochiltree Street
Nacogdoches, Texas 75961
Telephone: (936) 715-9333
Facsimile: (936) 715-9339
www.rankinlawfirm.com
-- 
To unsubscribe, e-mail: opensuse+unsubscribe@xxxxxxxxxxxx
For additional commands, e-mail: opensuse+help@xxxxxxxxxxxx