Larry,
good to see you here!
Of course, I have some comments on your suggestions :-)
> On 22 Jul 2020, at 21:14, Larry Wall <la...@wall.org> wrote:
>> Trick #5: -a
>>
>> -a turns on autosplit mode – perl will automatically split input
>> lines on whitespace into the @F array. If you ever run into any advice
>> that accidentally escaped from 1980 telling you to use awk because
>> it automatically splits lines into fields, this is how you use perl
>> to do the same thing without learning another, even worse, language.
>>
>> As an example, you could print a list of files along with their link
>> counts using
>>
>> ls -l | perl -lane 'print "$F[7] $F[1]"'
> This feature was always a bit suspect because it hard-wired a particular
> name. You don't even need a weird name in Raku:
>
> ls -l | raku -ne 'say "$_[7] $_[1]" given .words'
ls -l | raku -ne 'put .words[7,1]'
"put" stringifies a slice with a space in between elements.
>> Trick #6: -F
>>
>> -F is used in conjunction with -a, to choose the delimiter on
>> which to split lines. To print every user in /etc/passwd (which is
>> colon-separated with the user in the first column), we could do:
>>
>> perl -F: -lane 'print $F[0]' /etc/passwd
>
> Again, we felt this switch wasn't really pulling it's weight, so we pulled it
> in favor of explicit split or comb:
>
> raku -ne 'say $_[0] given .split(":")' /etc/passwd
raku -ne 'say .split(":").head' /etc/passwd
"head" takes the first element of a Seq *without* needing to cache it, making
it about twice as fast.
Liz
