My first response would be why? map is used (usually) when you want to modify a list of values and use the modified list. In my opinion, what you are doing is clearer being done with a for loop.
Reformatted:
my @names = map { # 1, 3
$i > 6 # 2, 4
? push(@names,$input2arr[$i]) # 1, 2
: $i++; # 2
} @input2arr;
- 1) You are assigning the results of the map call to @names and modifying it within the map call. Don't do that. It will not do what your original for loop does.
- 2) push returns the number of elements after the push in @names. The tristate ( A ? B : C returns either the size of @names when a push happens, or the value of the counter $i.
- 3) @names, I believe, will end up with the value ( 0, 1, 2, 3, 4, 5, 6). It is also possible that it is undefined behavior.
- 4) $i is not defined. I am assuming that, in numeric form, it starts at 0.
If you didn't want to use the for construct, perhaps the 'x' operator, splice, or even a straight assignment would be better.
Update: Since others posted before I completed mine, this block of code illustrates what you would be seeing:
@x = map {
$r = push(@x, $_);
print(join(",", @x),"\n");
$r;
} qw(a b c d e);
print join(",", @x), "\n";
__DATA__
a
a,b
a,b,c
a,b,c,d
a,b,c,d,e
1,2,3,4,5
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