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Set by lizmat on 8 June 2022.
01:30 m_athias left 01:31 m_athias joined 03:19 deoac left 06:42 kjp left 06:47 kjp joined
jaguart argh - I've just discovered that the conference day1 was yesterday! I thought is was Sat-Sun, and the email arrived saying 15:00 UTC... so I assumed Sat 16:00BST for me. :( will have to watch it on rewind 09:44
oh wait - today is already Sunday :o 09:45
I think I'm lost in time...
Nahita :p 09:50
jaguart m: say Version.new('1.2.3').Str 09:59
camelia 1.2.3
jaguart m: say Version.new('1.2.3').gist
camelia v1.2.3
jaguart m: say Version.new('1.2.3') 10:00
camelia v1.2.3
jaguart this confused me for a while
m: say Version.new('v1.2.3') 10:01
camelia vv.1.2.3
jaguart m: say Version.new('v1.2.3').parts.join: ' '
camelia v 1 2 3
lizmat jaguart: hope you're in sync again now :-) 10:29
jaguart extra coffee - catching up, 16:00 BST for the next zoom 10:30
Nemokosch imma fix your delorean if that helps 10:31
jaguart what would I use in a function signature for Int or Str-that-looks-like-Int, e.g. 0 or '0' 10:41
lizmat m: sub a(Cool:D $a) { dd +$a }; a 42; a "666" 10:46
camelia 42
666
lizmat jaguart ^^
jaguart That's Cool ;) thanks
lizmat this will also cover Num / Rat / Complex 10:47
Nahita also Lists and Hashes right 10:49
but `Int:D()` also accepts Lists and Hashes
jaguart nice :) 10:51
m: sub x(Cool $a){ say $a,' is ',$a.^name };x(1);x('1');x('1.1.1');
camelia 1 is Int
1 is Str
1.1.1 is Str
Nahita maybe `sub f($arg where * %% 1) { ... }`
maybe `sub f($arg where * %% 1) { ... }` but this also accepts lists and hashes 10:53
ok my overkill is `sub f(Int:D() $arg where {($_ ~~ Str|Int) && ($_ %% 1)}) { $arg.say }` 10:55
in an attempt to "need an Int or Str which in numeric context equals to itself when decimals are removed; then coerce to integer" 10:58
jaguart Nahita - thanks 😮 11:05
Nahita ok my overkill is `sub f($arg where {($_ ~~ Str|Int) && ($_ %% 1)}) { $arg.say }` 11:10
in an attempt to "need an Int or Str which in numeric context equals to itself when decimals are removed"
jaguart I asked yesterday about Moo lazy builders -> and was pointed to raku.land(Attribute::Lazy) - which is fab, so...
was hoping for the Moo handles -> qw/ list of methods /; - is there sugary syntax to proxy/delegate methods in Raku? 11:11
e.g. has $meta will lazy { META6.new( file => './META6.json' ) } handles qw/ version /; 11:12
which lazy-builds self.$meta and then passes calls to self.version through to $meta.version 11:14
Moo also does method aliasing by using a hash instead of a list - e.g. handles { version => ver, major => primary, } etc. 11:15
SmokeMachine m: class C { has Int $.a handles < is-prime >= 42 }; say C.new.is-prime
camelia False
jaguart Smokin! thank you 11:16
CIAvash docs.raku.org/language/typesystem#...it-handles
jaguart sorry - will search docs first next time!
CIAvash it's not a problem, there are just more examples there 11:19
jaguart I got caught by Attribute::Lazy being in raku.land and searched there, without thinking to go back to the docs. 12:46
Anyone know about latest spec for META6.json - I see that github.com/jonathanstowe/META6 talks about 'raku-version' but that the META6 package in zef has slightly tweaked key 'raku', and the docs all talk about 'perl'... 12:48
lizmat I just go by with what App::Mi6 gives me on a new module
:-)
jaguart Yeah - I've been using that too - but if I use META6 to load, read and write the META6.json I get a key-change 12:49
lizmat ah, intriguing
maybe skaji-san and rabidgravy should get in touch with each other :-) 12:50
jaguart hmmm - does that imply that all jonathanstowes like gravy?
lizmat you would need to ask them :-) 12:51
jaguart btw - a huge thank you for all you do for raku - everywhere I look I see your hands 🙏 12:52
deadmarshal What is the equivalent of Perl's ntheory module in Raku? 13:05
metacpan.org/pod/ntheory
lizmat jaguart: you're welcome :-) 13:08
deadmarshal: I don't think there is a 1-to-1 translation
deadmarshal lizmat: ok thank u 13:09
lizmat looks like it's no XS, so should be portable relatively easy, I'd say 13:10
deadmarshal What is the reason behind %% operator? cuz one can simply do for example num1 % num2 == 0. 13:16
lizmat well, the community wanted an operator to represent "is divisible by", and %% is just that 13:17
deadmarshal Seems useless xD 13:22
lizmat usefulness is in the eye of the beholder :-) 13:24
CIAvash I'm sure you write `$x = $x + 1` instead of `$x++`, because you can simply do that
deadmarshal $x++ situation is different because ++$x and $x++ makes huge difference. but %% not so much 13:27
CIAvash Then I guess you can also go and tell the Go community that their `x++` is useless because there is no `++x` in Go 😀 13:35
then there is `+=`, `~=`, `[op]=`, `<=`, `>=` and other useless stuff 13:43
Nahita m: my @arr = 1..50; (@arr X[%%] (3, 5)).rotor(2).kv.map({($^val<> RZx ("fizz", "buzz")).join or @arr[$^idx]}).say
seems useful to me :p
Nemokosch Insane stuff 13:46
Anyway, if you do anything with arithmetics, you'll appreciate %% 13:47
Literally, why would you refuse a gift like this
lizmat m: my @arr = 1..50; (@arr X[%%] (3, 5)).rotor(2).kv.map({($^val<> RZx ("fizz", "buzz")).join or @arr[$^idx]}).say 13:49
camelia (1 2 fizz 4 buzz fizz 7 8 fizz buzz 11 fizz 13 14 fizzbuzz 16 17 fizz 19 buzz fizz 22 23 fizz buzz 26 fizz 28 29 fizzbuzz 31 32 fizz 34 buzz fizz 37 38 fizz buzz 41 fizz 43 44 fizzbuzz 46 47 fizz 49 buzz)
Nemokosch Why is the reduction needed? 13:53
Nahita uh, it's not actually, i guess i tend to write operators in square brackets as normally we do to refer them shortly like `&[*]` instead of `&infix:<*>` so... 14:04
to my defense, `X[%%]` looks better than `X%%` :p
Nemokosch You can very well be right, I'm not actually sure if it is a reduction in that position 14:26
14:58 andm joined
andm hello, i have string 15:00
'[["03","18","1","731","97"],["06","17.6","2","730","97"],["09","18.4","2","730","98"],["12","23.3","4","730","83"],["15","27.6","5","729","60"],]'
is there a way to make raku think it's a raku code? 15:01
15:15 deoac joined
guifa_ andm: you can use EVAL (with, of course, all of the security implications that that involves) 15:16
m: use MONKEY-SEE-NO-EVAL; my $string = '[["03","18","1","731","97"],["06","17.6","2","730","97"],["09","18.4","2","730","98"],["12","23.3","4","730","83"],["15","27.6","5","729","60"],]'; say EVAL $string;
camelia [[03 18 1 731 97] [06 17.6 2 730 97] [09 18.4 2 730 98] [12 23.3 4 730 83] [15 27.6 5 729 60]]
guifa_ You're required to use `use MONKEY-SEE-NO-EVAL` because of those security implications. 15:18
andm guifa_, yes, it's works, thanks 15:21
deadmarshal CIAvash: that is becuz go itself is useless Xd 15:40
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CIAvash deadmarshal: I thought you would like Go, 'cause they share your way of thinking, "why X when you can simply do Y?" 16:26
deadmarshal I like Oberon :D 16:30
16:39 Kaiepi joined 17:00 andm left
Nemokosch which reiteration of Oberon? 18:14
deadmarshal 07 18:15
Nemokosch Tbh it looks worse than contemporary Pascal dialects at first sight 18:19
deoac ```
class Foo {
    has Int @.bar[5,5];
}
```
my $x = Foo.new;
$x.bar[0;0] = 42
Nemokosch 😅 18:20
deoac How can I write a postcircumfix operator so
$x[[0;5]]
does the same thing
?
Nemokosch first off, I'd hope if you can do it, you can do it without overriding the operator itself, just overriding the method doing the access 18:25
AT-KEY that is, had to check 18:26
do you mind if [0;5] is eventually [0,5] ? 18:30
I mean, they are literals for the same data
lizmat only superficially so 18:36
m: dd [0,1,2,3]
camelia [0, 1, 2, 3]
lizmat m: dd [0,1;2,3]
camelia [(0, 1), (2, 3)]
Nemokosch I know I know 18:49
with this particular data, they are the same, not that , and ; are interchangable
lizmat oki :-) 18:56
Nemokosch do you think I'm in the right with the general idea? 😛 18:57
Kaiepi the evil way would be to parse `qw` 18:58
deoac No, I don't mind using either a comma or semi-colon 19:00
But when I've used a comma, I get an error: "Partially dimensioned views of shaped arrays not yet implemented. Sorry." 19:01
Nemokosch no worries, I think it can be "implemented" 19:02
m: class Foo { has Int @.bar[5,5]; method AT-KEY(\key) { @.bar[||key] } }; my $x = Foo.new; $x[[0;5]] = 42; dd $x.bar; 19:16
aaalmost
okay, I'm getting an error that I cannot immediately comprehend 😅 19:18
okay... yes, this would be with {} outside, not [] 19:22
m: use 6.e.PREVIEW; class Foo { has Int @.bar[5,5]; method AT-KEY(\key) is rw { @.bar[||key] } }; my $x = Foo.new; my @idx = 0;5; $x{@idx} = 42; dd $x.bar; 19:25
m: use v6.e.PREVIEW; class Foo { has Int @.bar[5,5]; method AT-KEY(\key) is rw { @.bar[||key] } }; my $x = Foo.new; my @idx = 0;5; $x{@idx} = 42; dd $x.bar; 19:26
okay, let me dream big... 19:27
m: use v6.e.PREVIEW; class Foo { has Int @.bar[5,5]; method AT-KEY(@key) is rw { @.bar[||@key] } }; my $x = Foo.new; $x{[1; 2]} = 42; dd $x.bar; 19:28
Expected Positional but got Int 19:31
well, rip me. I have no clue why an Int got passed...
my best guess is that some sort of "single argument rule" applies, I don't know though 19:32
m: use v6.e.PREVIEW; class Foo { has Int @.bar[5,5]; method AT-KEY(@key) is rw { @.bar[||@key] } }; my $x = Foo.new; $x{([1; 2], )} = 42; dd $x.bar; 19:33
annoying 19:34
so the last one worked but it also got quite ugly
m: use v6.e.PREVIEW; class Foo { has Int @.bar[5,5]; method AT-KEY(@key) is rw { @.bar[||@key] } }; my $x = Foo.new; $x{$[1; 2]} = 42; dd $x.bar;
deoac: my best attempt probably 19:35
gotta wait for pros
19:45 Nemokosch joined, Nemokosch left
Kaiepi m:``` 20:10
only postcircumfix:<⟦ ⟧>(Mu \topic, @values is raw) { @values }
dd 1⟦[ 2, 3; 4, 5 ]⟧;
dd 1⟦( 2, 3; 4, 5 )⟧;
```
something along these lines?
not sure on how to do it w/o unicode without making it 6 characters 20:12
something with a signature along these lines?
Nemokosch so this is a brand new operator?
guifa_ AT-KEY is for hashy stuff 20:13
AT-POS is for listy
lizmat Associative actually
guifa_ hence the -y ;-) 20:14
Kaiepi partly. it wraps `[ ]`/`( )`, which does the dirty work with `;`
guifa_ Associative is like.... 6 letters more or something
lizmat hehe
Nemokosch yes, it was associative
but I don't think it would have worked with positional
hence with []
Kaiepi oh i see 20:18
hold on
oh that's cryptic 20:32
m:```
use v6.e.PREVIEW;
class Foo does Positional {
has Int @.bar[5;5];
method ASSIGN-POS(+@dimensions) {
@!bar.ASSIGN-POS: |my @[3] = @dimensions
}
}
my Foo $x .= new;
$x[0;0] = 1;
say $x;
```
it wants dimensioned arguments 20:33
Nahita m:`​`` 20:34
class F {
has @.arr[2;3];
submethod TWEAK {
@!arr := [[1, 3], [4, 5], [6, -1]];
}
}
multi sub postcircumfix:<[; ]>(F $obj, @indices) is raw {
callwith($obj.arr, @indices);
}
my $f = F.new;
say $f[1;1];
say $f[2;0] **= 3;
say $f;
`​``
m: `​``
class F {
has @.arr[2;3];
submethod TWEAK {
20:35 discord-raku-bot left, discord-raku-bot joined
m:``` 20:35
class F {
has @.arr[2;3];
submethod TWEAK {
@!arr := [[1, 3], [4, 5], [6, -1]];
}
}
multi sub postcircumfix:<[; ]>(F $obj, @indices) is raw {
callwith($obj.arr, @indices);
}
my $f = F.new;
say $f[1;1];
say $f[2;0] **= 3;
say $f;
```
Kaiepi (shouldn't have `does Positional`) 20:37
Nahita can these be done with `handles` i'm not sure
i.e., i don't know :p 20:38
Kaiepi i think that winds up an awkward `FALLBACK`
it needs a method name 20:39
it needs a method name to dispatch to generically
a method would need to take a method name to dispatch to generically
deoac How can you return an l-value? 21:43
That is, I want to modify the variable that's being returned. 21:44
Nemokosch my code had an example for that as well 21:45
Nahita's code as well
define the function as "is rw" (if its always an lvalue) or "is raw" (if it should be kept as-is)
gfldex deoac: see: docs.raku.org/language/control#ind...-return-rw 21:47
Nemokosch the way I understand it: if you pass a bare value to "is rw", it fails; if you pass it to "is raw", it won't fail but obviously you will only get the bare value back, without a container
deoac ah, thank you 21:51
Nemokosch Well we didn't use return so... yeah. 😄 There are two ways now, at least 22:00

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