Not even a reset- every time there's a $ by itself it is a new/different
anonymous variable. So it is only useful where it is never referred to
anywhere else.
$ raku -e "for (1..4) { say $++, ' , ', ++$; say 'again- ',$;}"
0 , 1
again- (Any)
1 , 2
again- (Any)
2 , 3
again- (Any)
3 , 4
again- (Any)
Hmm, how to make an alpha counter?
$ raku -e "for (1..4) { say ($ ||= 'AAA')++ }"
AAA
AAB
AAC
AAD
There is also anonymous @ and % but I don't have an example off the top of
my head.
-y
On Mon, Aug 31, 2020 at 4:57 PM ToddAndMargo via perl6-users <
perl6-users@perl.org> wrote:
> On 2020-08-31 16:53, ToddAndMargo via perl6-users wrote:
> >>> On Mon, Aug 31, 2020, 4:20 PM ToddAndMargo via perl6-users
> >>> <perl6-users@perl.org <mailto:perl6-users@perl.org>> wrote:
> >>>
> >>> On 2020-08-31 05:53, Brian Duggan wrote:
> >>> > On Monday, August 24, Curt Tilmes wrote:
> >>> >> $ cat Lines.txt | raku -e '.say for lines()[3,2,5]'
> >>> >
> >>> > The -n flag is an option here too:
> >>> >
> >>> > raku -ne '.say if $++ == 3|2|5' Lines.txt
> >>> >
> >>> > Brian
> >>> >
> >>>
> >
> >>>> Hi Bill,
> >>>>
> >>>> Works beatifically! And no bash pipe!
> >>>>
> >>>> $ raku -ne '.say if $++ == 3|2|5' Lines.txt
> >>>> Line 2
> >>>> Line 3
> >>>> Line 5
> >>>>
> >>>> What is `$++`?
> >>>>
> >>>> -T
> >>>>
> >
> > On 2020-08-31 16:36, yary wrote:
> >> $ by itself is an anonymous variable, putting ++ after starts it at 0
> >> (hmm or nil?) and increments up.
> >>
> >> By putting the plus plus first, ++$, it will start at 1, thanks to
> >> pre-increment versus post increment
> >>
> >
> > Hi Yary,
> >
> > Excellent instructions! It is a counter. I found
> > it over on
> >
> > https://docs.raku.org/perl6.html
> >
> > with a search on `$++`. But I had to pick it up
> > from "context"
> >
> >
> >
> > $ p6 'my @x=<"a" "b" "c">; for @x -> $i { print $++," ", ++$, " ", $i,
> > "\n";}'
> > 0 1 "a"
> > 1 2 "b"
> > 2 3 "c"
> >
> > Question: does the counter restart after its use, or do
> > I need to do it myself?
> >
> > -T
> >
>
> To answer my own question. It resets itself:
>
> $ p6 'my @x=<"a" "b" "c">; for @x -> $i { print $++, " ", ++$, " ", $i,
> "\n" }; print "\n", $++, "\n";'
> 0 1 "a"
> 1 2 "b"
> 2 3 "c"
>
> 0
>
>
>
> --
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Computers are like air conditioners.
> They malfunction when you open windows
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
