Maciej Kazulak wrote:
> That's how bash evaluates logic expressions. There's even a fancy word 
> for it i think. Point is it will execute commands only to the point 
> where it can determine the logic result. 

The fancy word for it would probably be short circuit evaluation:

http://en.wikipedia.org/wiki/Short-circuit_evaluation

When placing code in a boolean expression it is critical to understand 
whether the boolean operator will be evaluated in a short-circuit 
fashion in any language.

I'm not aware of any language that works this way, but potentially you 
could even have out-of-order boolean evaluation (ie echo "hello" && 
false does nothing) in a very well optimized language.

Using && in this way is technically a bit of a hack - the && operator 
was intended to evaluate a boolean expression and not as a replacement 
for "if".  That doesn't stop 99.9999999% of shell scripters from using 
it, however.  It is less of a hack than writing the equivalent of 30 
lines of code inside a for(<gobs of code> ; <gobs of code> ; <gobs of 
code>); statement in C.  :)