Re: HoA building

"CP" == Chad Perrin <perrin@xxxxxxxxxxxx> writes:

CP> On Wed, Dec 27, 2006 at 07:42:59PM -0500, M. Lewis wrote:
>> John W. Krahn wrote:
>> >M. Lewis wrote:
>> >>
>> >>while (my $ln = <DATA>){
>> >> chomp $ln;
>> >> my ($prod, $flavor) = split /\s/, $ln, 2;
>> >
>> >You probably should use ' ' instead of /\s/ as the first argument to split:
>> >
>> > my ($prod, $flavor) = split ' ', $ln, 2;
>>
>> Ok, but why? Are they not the same?

CP> No, they're not. ' ' is a literal space. /\s/ matches any whitespace.

' ' is not a literal space when used with split. first off, the first
argument to split is always a regex so use // instead of ''. but ' ' is
special (and only when in quotes) and it has several benefits:

from perldoc -f split:

As a special case, specifying a PATTERN of space (' ') will
split on white space just as "split" with no arguments does.
Thus, "split(' ')" can be used to emulate awk's default
behavior, whereas "split(/ /)" will give you as many null
initial fields as there are leading spaces. A "split" on
"/\s+/" is like a "split(' ')" except that any leading
whitespace produces a null first field. A "split" with no
arguments really does a "split(' ', $_)" internally.

uri

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