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Multiple conditionals in a while loop


 
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# 1  
Old 10-18-2007
Multiple conditionals in a while loop

Hi was wonderring about the syntax for the following peice of code:

while [[ $life != 0 || $mask != $word ]] ; do

This is apparently incorrect. I want the loop to continue WHILE $life is not equal to zero or $mask is not equal to $word. Should ONE of these conditions fail to be met, loop should break out. Any ideas?
thanks in advance: Sant
# 2  
Old 10-18-2007
Your logic is at fault. You want the loop to continue WHILE $life is not equal to zero AND $mask is not equal to $word.

De Morgan's laws - Wikipedia, the free encyclopedia

Last edited by Ygor; 10-18-2007 at 11:05 PM.. Reason: Added link.
# 3  
Old 10-19-2007
@OP, in my opinion, this construct is better. You don't have to "clutter" the while loop conditions.

Code:
while [True];
do
     if condition1 is true { break }
     if condition2 is true {break } 
     do_something...
done

# 4  
Old 10-19-2007
Using "break" violates good programming standards because it breaks the "single-entry single-exit" rule for control structures.
# 5  
Old 10-19-2007
looking at a bigger picture, if the programming language one is using doesn't "enforce" that, it doesn't really matter if one follows the "good" programming practice or not.
# 6  
Old 10-19-2007
# 7  
Old 10-19-2007

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