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Testing for no input.

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# 8  
Old 06-07-2005
Quote:
Originally Posted by jhansrod
Perfect... Thanks
Sorry, but I think there is a more elegant way: use the "${....:=...}" variable expansion. The expression "${var:=defaultvalue}" evaluates to the value of $var if $var is non-null (non-zero) or to defaultvalue otherwise. Here is an example:

Code:
typeset var="abc"
typeset foo=""
typeset bar=""

foo=${var:="def"}
print $foo              # will yield "abc", as $var was non-null
unset var
bar=${var:="def"}
print $bar              # will yield "def", as $var is not set now

bakunin
# 9  
Old 06-07-2005
Indeed, ${foo:=default} is the most elegant way of doing this (in shells that support it - ksh, bash, et al)

But, muthukumar, I'm curious why you "let var=3" when a simple "var=3" would do?

Cheers
ZB
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