With the Perl5 compiler the -n flag literally adds this around your code
before compiling:
while ( <> ) {
…
}
Rakudo handles -n by transforming the AST (or the bytecode) into something
that loops.
Basically it is more like:
… for lines
(In that it doesn't affect scoping or
> Could the "-e" flag be limiting variable initializations to one?
I don't think so. I recall the -n being shorthand for wrapping your -e program
in
while ( <> ) {
# your program here
}
(-p just adds a continue "print" block, I believe), as folks would do cool
tricks of writing their -e script
> I see that Int/Num error,
What platform are you using? I believe William Michels is on OSX.
> and also would like an explanation as to why "my
> Int $y" isn't re-initialized to Any each time through this loop
So the question is if "-n" is exactly equivalent to wrapping the
given code in a loo
Hi Yary,
Honestly, I just tried re-writing the fastest StackOverflow answer
(written in Perl 5) that I found below, in Perl 6. To write P5 as P6 I
had to declare the variable $x with 'my'. Then I played around with a
declaration restricting to "Int" type (to look at potential
performance hits), ju
Um, okay, But I'm still seeing the same behavior Andy is, using the
last rakudo star release 2019.03.1, Perl 6.d:
seq 100 | perl6 -ne 'my Int $y += $_; END { print $y; }'
5050
This is on linux, (32 bit Debian 9, aka stretch).
On 9/26/19, Andy Bach wrote:
>> Still, it's just
I see that Int/Num error, and also would like an explanation as to why "my
Int $y" isn't re-initialized to Any each time through this loop
$ seq 100 | perl6 -ne 'my Int $y += $_; END { print $y; }'
Type check failed in assignment to $y; expected Int but got Num
(5050e0)
in block a
Thank you, Andy and Joseph!
On Thu, Sep 26, 2019 at 8:47 AM Andy Bach wrote:
>
> > Still, it's just "works for me":
>
> seq 100 | time perl6 -ne 'my $y += $_; END { print $y; }'
>
> I think that's still the wrong one - your missing the "Int"
> $ seq 100 | perl6 -ne 'my Int $y += $_; END
> Still, it's just "works for me":
seq 100 | time perl6 -ne 'my $y += $_; END { print $y; }'
I think that's still the wrong one - your missing the "Int"
$ seq 100 | perl6 -ne 'my Int $y += $_; END { print $y; }'
5050
though that works here, admittedly, my p6 is sort old
This is
