Re: perl streaming framework
Hi Warren! On Wed, 15 Jul 2020 08:43:33 +0800 Warren Pang wrote: > Thank you all very much. > > I have tried to search "perl discussion" and it brings me to perl6's list > page. > Yes for data analysis we primarily use classic perl5, which is smart enough > especially the regex matching. > There are "spark streaming", "flink streaming", "storm streaming", and a > lot of others, but they don't support perl language well. > So I expect the community, either perl6 or perl5, can make that a framework. "Perl 6" is now called Raku and is not compatible with Perl 5. Regarding "the community" making something - I recall a similar request (or was it a demand?) on a Perl facebook group that we must have a https://en.wikipedia.org/wiki/Massive_open_online_course (MOOC) for Perl. As usual with FOSS, time consuming suggestions can be materialised either by investing time, or by motivating contributors using money. Otherwise, they often don't get materialised. > We can't lose the capability in big data, cloud computing, AI, ML, > streaming, these are the main features of current internet. From what I know, not everyone is doing AI (which I was told requires a relevant M.Sc and has a high barrier to entry) and "machine learning" is not the only approach to AI: https://fc-solve.shlomifish.org/faq.html#machine_learning > Everyone today writes CGI with perl? NO. > Not everyone today writes CGI scripts, or uses Perl for them, but some people still do. These include me because I prefer to use shared web hosting, where, for server side scripting, I can use either PHP (which I dislike, see: https://www.shlomifish.org/open-source/anti/php/ ) or CGI scripts (in Perl or Python or similar). So I still use two such scripts in Perl and one which I translated from Perl to Python (not because I was unhappy with the Perl code, but because I've been trying to learn Python better) along with many generated static pages and assets here: * https://www.shlomifish.org/meta/site-source/ I was once told that generated static HTML should be avoided because PHP is the present and the future, but it seems they were proven wrong too: * https://github.com/shlomif/shlomif-tech-diary/blob/master/static-site-generators--despair.md I'm not saying server-side-scripting is not useful, but generated static sites are still of utility as well. > Thanks. -- Shlomi Fish https://www.shlomifish.org/ My Photos - https://www.flickr.com/photos/shlomif/ “Stop reinventing wheels, start building space rockets.” — The motto of the Comprehensive Perl Archive Network Please reply to list if it's a mailing list post - https://shlom.in/reply .
Re: proto and multi
Reviving this thread...
Synopsis: the previous discussion revolved around an error seen with a
whatever-star of the format "{ * }" (with spaces around the star). The
error was corrected by removing the spaces to use the whatever-star
"{*}" format.
So why then does the Raku NativeLibs module say to use the "{ * }" format?
See:
https://github.com/salortiz/NativeLibs
>From the ReadMe.md:
use NativeLibs; # This also re-exports NativeCall :DEFAULTS for
conveniencemy $Lib; # To keep the reference
sub some_native_func() is native { * } # Note no library needed
… The rest of your module
INIT {
# Load the needed library
without $Lib = NativeLibs::Loader.load('libsomelib.so.4') {
.fail;
}
}
…
It seems that some of these tiny differences--such adding a space or
two--could end up being a very off-putting source of frustration for people
who are just starting out (and even for experienced programmers as well).
Best, Bill.
W. Michels, Ph.D.
On Mon, Jun 29, 2020 at 11:32 AM Fernando Santagata <
nando.santag...@gmail.com> wrote:
> On Mon, Jun 29, 2020 at 8:22 PM Richard Hainsworth
> wrote:
>
>> a) I don't understand why the white space matters, but clearly it does.
>> So the token is '{*}' and not braces around a Whatever-star.
>>
> For an explanation see the thread "Playing with protos and phasers" that I
> started here three days ago.
>
> b) Removing the space yields the following response.
>> in string
>> Cannot resolve caller handle(NewClass:D: List:D); none of these
>> signatures match:
>> (NewClass: Str $s, *%_)
>> (NewClass: Positional @s, *%_)
>> in method handle at test.raku line 15
>> in block at test.raku line 30
>>
>> Not sure why the List:D is not being matched to Positional. Is the List:D
>> refering to the |c signature capture ??
>>
>> Since 'in string' was printed, one of the methods was reached. Confused.
>>
>> c) Writing out all the code in each method is what I already have. But
>> I'm looking for ways to factor out common code.
>>
>> Regards
>> On 29/06/2020 18:44, Fernando Santagata wrote:
>>
>> After deleting the spaces as suggested, there's a "Positional" too many.
>> I guess you can rewrite that method declaration as
>>
>> multi method handle(@s)
>>
>> or
>>
>> multi method handle(Positional $s)
>>
>> and adjust the method's body.
>>
>> On Mon, Jun 29, 2020 at 7:37 PM yary wrote:
>>
>>> It looks like you have spaces in the token { * } can you try it without,
>>> using this {*} instead?
>>>
>>> On Mon, Jun 29, 2020, 1:29 PM Richard Hainsworth
>>> wrote:
>>>
I have several multi methods.
All of them have the same first statement, then differ depending on the
signature.
proto seems to be a way to factor out the common statement, and there
is a phrase in the Documentation that * can affect the dispatch, viz:
"You can give the proto a function body, and place the {*} where you
want the dispatch to be done. This can be useful when you have a "hole" in
your routine that gives it different behavior depending on the arguments
given:"
The docs give and example proto, but unfortunately, not how this works
with other multi's.
So I tried this:
class NewClass {
has $.debug is rw = False;
has $.value is rw = 'Initial value';
proto method handle( |c ) {
note "value is $.value" if $.debug;
{ * }}
multi method handle(Str $s) {
$.value = $s;
say 'in string'}
multi method handle(Positional @s) {
$.value = @s[0];
say 'in positional'}
}
my NewClass $x .= new;
$x.handle('hello world');$x.handle();$x.debug =
True;$x.handle('hello world');$x.handle();
#raku test.raku
#value is Initial value
#value is Initial value
I am wondering how to use proto and {*}
>>
>> --
>> Fernando Santagata
>>
>>
>
> --
> Fernando Santagata
>
