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Re: anything faster than say [+] lines?

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From:
Joseph Brenner
Date:
September 25, 2019 23:57
Subject:
Re: anything faster than say [+] lines?
Message ID:
CAFfgvXULSJef93-w2_5S_KiLi48ArZ=YoM4VX08HC9m6R-p0pg@mail.gmail.com
I just gave that one-liner a try, but I didn't see that error:

> seq 1000000 | time perl6 -e 'say [+] lines'
500000500000
28.70user 0.07system 0:28.29elapsed 101%CPU (0avgtext+0avgdata
74188maxresident)k
63424inputs+0outputs (32major+15409minor)pagefaults 0swaps


perl6 --version
This is Rakudo Star version 2019.03.1 built on MoarVM version 2019.03
implementing Perl 6.d.

uname -a
Linux fandango 4.9.0-8-686 #1 SMP Debian 4.9.144-3 (2019-02-02) i686 GNU/Linux



On 9/24/19, William Michels via perl6-users <perl6-users@perl.org> wrote:
> I'm seeing a strange error. I started trying out Marc's original code,
> then tried to adapt some Perl5-type solutions from SO to see how they
> performed when re-written as Perl6. One thing I wanted to explicitly
> test was how restricting to an "Int" type affected performance.
>
> However, I found a surprising result: a sequence of one-million Ints
> throws an error, but a sequence of 999,999 Ints does not:
>
>> mbook:~ homedir$ seq 1000000 | time perl6 -e 'say [+] lines'
>> 500000500000
>>         4.81 real         4.86 user         0.20 sys
>> mbook:~ homedir$ seq 1000000 | time perl6 -ne 'my $y += $_; END { print
>> $y; }'
>> 500000500000        4.88 real         5.06 user         0.19 sys
>> mbook:~ homedir$ seq 1000000 | time perl6 -ne 'my Int $y += $_; END {
>> print $y; }'
>> Type check failed in assignment to $y; expected Int but got Num
>> (500000500000e0)
>>   in block <unit> at -e line 1
>> 499999500000        4.77 real         4.97 user         0.19 sys
>> mbook:~ homedir$ seq 999999 | time perl6 -ne 'my Int $y += $_; END { print
>> $y; }'
>> 499999500000        4.86 real         5.05 user         0.19 sys
>> mbook:~ homedir$ perl6 -v
>> This is Rakudo version 2019.07.1 built on MoarVM version 2019.07.1
>> implementing Perl 6.d.
>> mbook:~ homedir$
>
> Any comments or explanation appreciated,
>
> Best Regards, Bill.
>
>
>
>
> On Tue, Sep 24, 2019 at 1:59 AM Marc Chantreux <eiro@phear.org> wrote:
>>
>> hello,
>>
>> > > > > nice ... but when x is ~ 75440 (not always), there is a problem
>> > > > What is x here?
>> > > sorry. x is the arg of seq (number of lines).
>> > That never happens on my laptop
>>
>> well.. so it's a problem with my station. nevermind :)
>>
>> thanks again for helping
>> marc
>

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