Hi all,

Tis late on POETS day and not untypically, I've encountered a problem - which is a seeming oddity in the behaviour of grep - let me explain (which, if I don't, won't win me any friends;-)

There's something odd in the way that grep is behaving in the following... 

grep /\Q$choice\E/, @REPORT && do {
    last READ_LOOP;
};

[download]
Irrespective of the values of $choice and @REPORT, the last statement is always reached (and executed).

However, if the statement is re-written slightly - to add parenthesis for the arguments to the call to grep: 

grep(/\Q$choice\E/, @REPORT) && do {
    last READ_LOOP;
};

[download]
All of a sudden, the last statement is conditionally reached i.e. is now dependent on the values of $choice and @REPORT. For information, $choice typically contains either a path or a digit but, as was said in Airplane, that's not important right now:-)

B::Deparse provides further information: 

user@unforgiven:~$ perl -MO=Deparse -e 'grep /\Q$choice\E/, @REPORT &&
+ do {
    last READ_LOOP;
};'
grep /\Q$choice\E/, @REPORT && do {
    last READ_LOOP
};
-e syntax OK

user@unforgiven:~$ perl -MO=Deparse -e 'grep( /\Q$choice\E/, @REPORT) 
+&& do {                  
    last READ_LOOP;
};'
if (grep /\Q$choice\E/, @REPORT) {
    last READ_LOOP;
}
-e syntax OK

[download]
Armed with this information, I still can't see why perl interprets the 2 non-equivalently.

I'm sure this is but a small copse, but still I can't see the wood for the trees ... would anyone be good enough to enlighten me ?

TIA ,

A user level that continues to overstate my experience :-))

In reply to Alas poor grep, I thought I knew him well.. by Bloodnok

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