Hello hghosh,
how would I use $line directly in the while condition? And what makes that better than declaring it as I did?
I think LanX is recommending something along these lines:
while (my $line = <IN>) {
chomp $line;
...
which is simpler and clearer.
Also, if I left $_ as it is in the second, strictured code block, it would refer to the same $_ as the first block of code, right?
Not sure which blocks you’re referring to; but, just to be clear, $_ refers to the “current” (i.e., the most closely related) syntactic construct that sets it. For example:
use strict;
use warnings;
for ('A' .. 'C')
{
print "Outer: \$_ = $_\n";
for (10 .. 12)
{
print " Inner: \$_ = $_\n";
}
print "Outer: \$_ = $_\n";
}
produces:
23:21 >perl 2004_SoPW.pl
Outer: $_ = A
Inner: $_ = 10
Inner: $_ = 11
Inner: $_ = 12
Outer: $_ = A
Outer: $_ = B
Inner: $_ = 10
Inner: $_ = 11
Inner: $_ = 12
Outer: $_ = B
Outer: $_ = C
Inner: $_ = 10
Inner: $_ = 11
Inner: $_ = 12
Outer: $_ = C
23:22 >
— showing that there are actually as many independent instances of $_ (two, in this case) as the scoping requires.
Hope that helps,
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