Re^3: csv to hash table

You're confusing the filehandle with the record being read.

Using more code than is really necessary to demonstrate the point:

open my $filehandle, ...

while (my $record = <$filehandle>) {
    chomp $record;  # Remove the newline
    # Do stuff with the record text, e.g.
    my @fields = split /$field_separator/ => $record;
    ...
}
[download]

That would normally be coded more succinctly as:

open my $filehandle, ...

while (<$filehandle>) {
    chomp;  # Remove the newline
    # Do stuff with the record text, e.g.
    my @fields = split /$field_separator/;
    ...
}
[download]

In the second code fragment, all instances of $record (from the first fragment) are now $_, which (being the default for chomp, split, and many other functions) can be omitted.

And, just in case it wasn't obvious, that was for general enlightenment, not a recommendation to attempt your own version of Text::CSV. :-)

-- Ken

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Re^4: csv to hash table by GrandFather (Saint) on Nov 19, 2013 at 20:18 UTC
Why `=>` in `split /$field_separator/ => $record`? To my eye that says paired item, but there it's just a plain ol' comma and would be clearer as: `my @fields = split /$field_separator/, $record;` [download] Personally I prefer making the record variable explicit, but I'd write the while expression as: `while (defined (my $record = <$filehandle>)) {` [download] which is a closer match to the magic you get with `while (<$filehandle>) {`. True laziness is hard work	[reply] [d/l] [select]
Re^5: csv to hash table by kcott (Archbishop) on Nov 20, 2013 at 06:18 UTC
"Why `=>` in `split /$field_separator/ => $record`?" Beyond being a preferred style, it has no particular significance. "To my eye that says paired item, but there it's just a plain ol' comma and would be clearer as: ..." I really can't believe you're having any difficulty with the clarity of that code; however, if you are, think of it in terms of this pairing: how to split `=>` what to split With regards to the `while` condition, my intention was to point out the confusion between the filehandle and the record. I thought I'd made that fairly clear with my opening sentence. I didn't consider a more in-depth discussion of how `<$filehandle>` works to be useful or helpful in this context. [To waytoperl: If you're wondering about this use of defined, it's explained in more detail in perlop: I/O Operators.] -- Ken	[reply] [d/l] [select]