00:00:06.080
hello everybody uh usually I put a slide greeting people in their native language
00:00:12.559
usually I don't know it at all but today so it happens that I'm a master of
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Bulgarian uh usually I also have slides explaining my name but I think today
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this is kind of redundant my friends uh especially those
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from turn from the high school typically call me bug but you can also call me Bojo
00:00:35.440
because you know Bojo is not a boo uh more boring slides that you
00:00:41.520
probably don't need an important slide usually I look better today however I had to wake up at
00:00:50.399
6:30 a.m. because yesterday I was at uh the Strasburg Christmas Market with a
00:00:56.960
dear friend of mine before this I taught my goddaughter some important life
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lessons because she's turning 10 this week and uh she's
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ready uh she was way too ready uh and uh this is why today I have
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a slight hangover because she's 10 but I am
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40 and uh yeah uh gady is a dear friend
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of mine as well this is why I inflicted myself the pain of coming uh from France
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today uh and you know we have been discussing uh doing something at Ruby
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banit for a very long time and I think I never came that's what she
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said but anyways uh this year because I'm older and uh maybe wiser I'm here
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whether I'm Wiser or not is debatable because I did watch the second part of Rebel Moon
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twice ah not twice uh and I did reread
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finally after 20 years of suffering The Wheel of Time this was a
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big mistake uh uh I knew I would regret it uh but there is something uh deeply
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broken um in me anyways I told you I have some drinking issues gady told me not to
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discuss drinking issues on the conference it's fine um and here is a snapshot of
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my interests in life uh this is my Instagram you see that uh I like uh I
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like watches I like o I'm not sure who this guy is I know
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it's talk man it's talk I have no idea who he
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is yeah but uh you know this is the thing about being in program pramming in your 40s at 20 you care about being a
00:03:05.599
better programmer you care about the craft uh about design patterns uh idioms
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uh best practices at 30 you realize this is kind of pointless maybe you decide
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that you want to try to be a manager and bring more impact uh Through Your Divine
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leadership style at 40 you realize that the only important thing in life are
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mean watches true story I'm uh really
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obsessed like I watch Apocalypse Now and uh all I'm thinking is damn uh Captain
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ward has a really good example of Captain Ward this is the Seiko
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6105 a legendary dive watch the second dive watch to be produced by
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Seiko and um the film makers really Led Watch is because you can see that kinel
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CTS Maron Brando wears a Rolex which is the arch nemesis of
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Seiko this is the GMT Master 2 I think so a very evil watch and why am I saying
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this because Ruby originates in Japan Seiko also originates in Japan and uh by
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trying a lot of watches I have scientifically concluded that I am 20% more program uh productive when I'm
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wearing a SEO like this one uh it makes me a better presenter as well I have
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also concluded that wearing a Casio makes me 30% more productive but I
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didn't have any Casio with me today so this is not going to be my best talk I can uh tell you more about
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watches uh about uh what they present for your fun level social status uh but
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uh the only person in the Ruby community that U appreciates uh my jokes about um
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watches is sadly not here so I'll switch to more boring and more educational
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topics so yeah uh genady alluded that uh I'm am supposedly known for working on
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some open source projects uh RoboCop is Alive and Well I
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know I'm supposed to say something about it uh this year the big news is that we
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support prism which is nice and rubocop is faster than ever in case
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it wasn't fast enough for you already so I'd say great
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success uh another interesting Milestone is that rubocop turned 12 years um in
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April quite earlier this year and uh next year will be I guess uh pretty
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critical for the future C birthday uh so yeah lots of lots things
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to celebrate also before this talk I checked that uh this is uh the total
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number of downloads so if somebody wants to nudge us over the
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edge impossible is nothing um this slide I forgot to update
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so I'll conveniently skip it um but uh yeah it has been a wild
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right uh during those past 12 years um RoboCop made it uh in the list of um
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alltime 100 gems in terms of downloads and if you look around it you'll see
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that most of the gems around it are just troc cops dependencies like progress bar
00:06:44.560
as rainbow so we propelled a lot of gems into into
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Fame uh you know but there is an actual talk today and uh I think the topic is um
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kind kind of interesting I want us to talk a little bit about some weird
00:07:06.120
aspects of Ruby uh in case you didn't notice I'm a weird person so I like
00:07:12.840
weird stuff that's why most of my presentations in the past 10 years have started with dictionary definitions
00:07:19.680
because why not uh so if you consult um one
00:07:25.160
dictionary I forgot which one about uh the word weird you'll see that um it can
00:07:32.160
be described as um something of strange or extraordinary
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character uh something of or relating to or caused by witchcraft or the
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supernatural this sounds very appropriate when we're talking about programming another dictionary
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definition very strange and unusual unexpected and uh or not
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natural so good stuff good stuff here and uh if we um if we try to find
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something about Ruby itself I guess the best uh way to describe it would be um
00:08:12.120
this blurp from uh Ruby link.org a dynamic open source programming language
00:08:18.319
with a focus on Simplicity and productivity it has an elegant syntax in
00:08:23.720
syntax uh that is natural to read and easy to write I have to tell you I am
00:08:30.039
impressed that I can even speak in uh English in my present state but you
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probably can't tell this so the important thing before we dive into this talk is that weird is not the same as
00:08:43.440
bad I have a bad Ruby talk as well and it is brutal this is a positive talk
00:08:50.680
weird is good Weir is also subjective um and uh if you ask
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different people about what aspects of Ruby do they find to be weird you're
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going to find always different answers I guess I was kind of uh lazy and U I
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thought let's ask uh the world's foremost expert on rubby what are the 10
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most weird features so I use this prompt uh and I got the following
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answers number one monkey patching weird stuff
00:09:30.160
number two open classes number three symbols yeah I was like okay that's
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weird um not the symbols blocks procs and
00:09:46.200
lambdas number five method missing number six meta
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programming number seven so this was very funny because chat GPT callede this
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Flex I syntax it's like okay whatever o your
00:10:04.480
boat number eight implicit returns oh
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yeah uh this was uh also a bit hard to parse at first self context changes uh
00:10:19.320
but basically this is the fact that self is different in different
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parts of the code um and uh fin fin number 10 keyword arguments with default
00:10:32.800
Val I was like okay okay so I used to be worried about
00:10:38.320
chat GPT but I think we are going to have jobs for at least two three years more which is a good thing and that's
00:10:45.680
all I have for you today let's go to the
00:10:54.279
restaurant there are 105 slides more
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and that unfortunately is not a joke my friends so uh Ruby is uh in its
00:11:09.639
managerial age 31 good age good age you can still drink reasonably
00:11:16.839
well and uh you are not afraid to go to a conference after
00:11:22.519
party so uh I'm a big fan of Batman and um I have
00:11:28.959
learned a lot about life for various Batman movies and comic books most importantly
00:11:36.360
I learned from uh The Dark Knight which I watched seven times in one week that
00:11:42.720
whatever doesn't kill you simply simply makes you weirder and uh if you're
00:11:49.720
31 clearly you survived a little bit in the world and you must have become quite
00:11:56.839
quite weird so um I do think that um a lot of the weirdness in Ruby is just a
00:12:03.600
function of its age 31 years uh for a programming language is like 300 years
00:12:09.320
for a human so it's a pretty good age so
00:12:14.880
how is this talk going to proceed uh there are going to
00:12:19.920
be different things that I think are weird and I'm going to be showcasing
00:12:26.839
showcasing them to you I'm going to classify those using three levels of
00:12:33.440
weirdness number one everybody knows what and I will be marking this with the
00:12:40.959
F in emoji nothing surprising the second level which is
00:12:47.720
more weird weirder is going to
00:12:53.800
be okay we're not going to pause this and we are going to fix it this
00:13:00.560
uh or uh as we say in
00:13:06.839
Bulgaria and uh level three in
00:13:12.360
English let's say it's uh holy and in Bulgaria it's going to be
00:13:20.000
z uh and because I wanted to incorporate madona in this presentation you know I
00:13:26.160
have this uh weird friend from sard um who always gets um shocked by some
00:13:34.240
weird stuff and says Madonna uh you I thought this is appropriate thing to do and I don't know
00:13:41.920
maybe a little bit uh less explicit so uh we are going to start
00:13:48.920
with a little bit of calibration I'm going to discuss a few
00:13:54.120
well-known examples of weird functionality in Ruby and we are going
00:13:59.519
to rank it together before before we dive into the weirder stuff so what do I
00:14:06.160
mean by those uh usual things like people often uh uh say that it's
00:14:14.720
kind of weird that in Ruby you can alter the natural uh flow of control meaning
00:14:21.000
that with end and begin blocks you can basically execute this bit of code
00:14:29.440
before the puts and this bit of code after everything else so we are not
00:14:35.880
executing it sequentially um whether you should be using this is
00:14:42.839
highly debatable but it is here for illustrative purposes so how weird do
00:14:49.000
you think this is other langu they yeah yeah I I think
00:14:57.360
this was copied from Pearl so definitely not uh not
00:15:03.000
groundbreaking uh this is the infamous flipflop operator that everybody knows
00:15:08.600
about nobody has used except whoever wrote this snippet that I have seen in
00:15:14.440
10 different books on Ruby maybe it's good also for um those uh programming
00:15:22.040
competitions to write the obfuscated code I forgot the name very popular in Japan
00:15:31.519
uh they had some
00:15:37.800
terminology uh you remember this we were at this uh competition when there
00:15:43.880
were maybe I forgot it but this is um
00:15:49.560
more than one because I think people use this you're the only one with that needs to De with other no I think it's a lot
00:15:56.600
just because everybody knows it yeah but I don't know I think this is uh
00:16:05.000
this is maybe a bit more interesting U you know I hope you know or if you don't
00:16:10.480
know it it's good for you that there is a different way to write comments in Ruby uh so-called begin end comments but
00:16:18.440
uh there is a weird thing about them if you don't place them at the very beginning of a line they don't work uh
00:16:24.800
this is a syntax error yeah I think uh this right uh
00:16:34.199
and this actually works but I would personally think it's broken
00:16:40.920
so yeah I um I also find it very weird that U we still have in
00:16:48.839
Ruby yeah yeah they used to be meaningful in the earlier days of Ruby
00:16:55.639
up to Ruby 1.8 but now there essentially um an
00:17:01.720
alternative way to write a single character string U not very weird but um
00:17:09.520
somewhat weird of course you can also use them uh for U slightly weirder
00:17:18.480
yeah um I I I learned a lot of weird
00:17:26.679
working on rubocop uh I have a attack weird Ruby in the issues
00:17:34.080
and every time I need to update this presentation I just uh scroll through
00:17:39.520
the last 10 20 issues good stuff anyways uh let let's continue calibrating
00:17:46.000
ourselves um re assignable con constants I think that uh the name alone is a
00:17:53.480
strong indication that something is uh very weird here at I hope you're all
00:18:00.840
aware and um you all agree with this we continue class variables I think they're
00:18:08.320
very well known not uh super weird know that's a
00:18:14.760
l and uh we kind of fix them in Ruby 3 this is
00:18:21.520
uh the point of this slide you are going to start getting an error that you
00:18:29.360
wouldn't be getting in the past if you decide to do something that looks
00:18:36.080
dangerous so uh they I'm trying to say that they're not as problematic as before so
00:18:43.240
maybe at some point people are going to start using them more I had um
00:18:49.559
completely uh missed this change in Ruby and I learned about it when um I got a
00:18:55.360
ticket should we unbun uh variables because it seems they're not as
00:19:00.880
dangerous as in the past so you know we keep learning new stuff every
00:19:08.720
day okay so small calibration exercise completed let's start getting more weird
00:19:16.600
I'm going to be showing you examples and uh you are going to be
00:19:22.120
telling me how weird they are so uh what does this bit of code uh return as the
00:19:36.000
result you tell me I'm voting for false any other
00:19:42.600
opinions true false okay any anything
00:19:54.679
um yeah so this can be only true
00:20:00.120
because this is those are the rules of
00:20:06.559
Precedence yes yes uh it's not needed uh
00:20:11.760
at um yeah Master programmer this is not looking good for
00:20:17.720
you but uh this is the same same
00:20:23.360
thing true or false true or false I'm not anymore
00:20:32.480
yes sir this is false because the operators are the same but somebody decided that the rules of Precedence are
00:20:40.400
different basically uh the ERS ERS version and the bar bar or however this
00:20:47.400
is called in English bind uh um the end
00:20:52.880
has a higher precedence than or but um with their English word versions they
00:20:59.000
have the same precedence and they're bind from left to right which uh which
00:21:05.520
results in some very confusing behaviors so for me this is this is a madona
00:21:12.960
moment u i we continue how many of you know what
00:21:21.159
this
00:21:26.480
is it's a it's three letters
00:21:31.520
technically okay
00:21:37.679
so madon um okay so it's basically something that really
00:21:45.400
looks like a hash and has your environment variables
00:21:50.640
there um but um if you check it's class
00:21:56.840
I know it what object you see this a monkey packaged object yes
00:22:08.720
yes I redeemed myself okay you redeemed yourself my friend okay so more quiz
00:22:15.320
questions uh I think this talk is working a lot better with uh people yes
00:22:21.440
yes yes uh what is uh what do you see
00:22:30.080
I know this this is an OCT number
00:22:35.400
Z so what is it in decimal
00:22:42.480
15 he unredeemed
00:22:47.720
himself yeah when I first saw this I felt like this
00:22:53.960
bear uh who the guy the guy who who was sitting on the
00:23:00.799
I was the bear I was the bear I'm a very violent person um you know I used to
00:23:06.080
play a lot of uh Warcraft 3 and I was pretty good at the height of my career I
00:23:11.240
made it to top 50 in the on the European ladder but I broke so many keyboards
00:23:16.720
after this point I realized I can never be a professional gamer so I became a programmer
00:23:24.120
instead yeah yeah I was uh very very V night
00:23:29.760
elf okay so um there is an alternative Syntax for this which I think reads a
00:23:36.799
lot better and um actually it's kind of consistent with the alternative syntax
00:23:44.279
with the not alternative but the standard Syntax for binary and uh for
00:23:50.200
hex decimal so you know I found it weird that they decided to treat um the octal
00:23:59.159
um uh digits um de octal numbers differently and yeah that's Ruby we have
00:24:05.840
weird stuff so tell me will this bit of code compile or
00:24:16.960
not yeah otherwise it wouldn't be
00:24:24.559
here will this bit of code compile oh
00:24:30.120
no do I see a yes I I yes okay let's uh
00:24:36.279
let's do a show of hands how many people think this is going to compile I I will do it okay
00:24:42.640
five six okay so it seems we split
00:24:48.080
evenly no no it wouldn't it wouldn't uh there there is a special handling um for
00:24:55.840
if that doesn't extend to other
00:25:03.039
keywords um no you cannot start with numbers
00:25:08.919
yeah so R from you I expect it more than from
00:25:14.760
genady I haven't drink any okay so um is this a valid bit of
00:25:23.799
cod yes no oh is this will be a valid one because you because of
00:25:30.720
the so this is UN those are two unes so do you really trust this guy after all
00:25:37.520
the mistakes he made this is my vote I I would say this is a valid for me okay and is this
00:25:48.480
valid I would say this is valid to be which
00:25:55.039
probably it is actually valid okay and it's valid for a very simple
00:26:01.480
reason um oh see Redemption uh so any
00:26:07.600
such bit of code essentially evaluates to X and uh this is where um I mentioned
00:26:14.960
that U you know Twitter these days is name Tex and it's and I'm on Blue
00:26:21.159
Sky which is blue and great I'm also on Mastodon at mostly on Blue Sky
00:26:29.080
I expect 20 new followers after the end of This brilliant talk
00:26:37.159
uh make it
00:26:43.880
happen get creative get creative okay we are going to the really good stuff
00:26:49.600
objectoriented negation so um a little known thing in Ruby is that the negation
00:26:56.320
operator is actually a standard method and you can write
00:27:01.799
like this and uh it will actually work not
00:27:07.720
very shocking right but uh you can also um override
00:27:14.279
it and you can calculate factorial in a really sexy way but I definitely don't
00:27:21.600
recommend doing this at home because your code is not going to behave very
00:27:26.840
well if you do it um so other things that I find
00:27:33.279
interesting um I guess everybody knows that um numbers have a natural order to
00:27:40.240
them and um you can generate a range of
00:27:46.200
numbers this is U backed internally by the suck method which doesn't suck but
00:27:54.000
it succeeds it's a very successful method that doesn't suck um and you know it is
00:28:01.760
used internally in ranges as I mentioned but um you can also use suck for
00:28:10.480
Strings and U the results might be somewhat um consistent or surprising
00:28:19.240
depending on the example or this one here okay maybe it's
00:28:26.360
okay here I'm not sure um and I know what um programmers
00:28:31.640
typically are thinking after they see this this is the best way to generate a
00:28:37.279
version a version range in Ruby and they write code like this and it works but
00:28:43.720
then they try it a little bit um more and the results are quite quite
00:28:51.760
surprising so yeah
00:28:59.799
don't do this don't do this uh I also did some um examples um in uh in
00:29:07.039
cic and uh the behavior was kind of weird here I was encouraged okay here I
00:29:14.640
was like I haven't seen this letter in cic yet and I remember when I was doing this
00:29:21.360
talk a bro people you have typos in your slides those letters don't exist
00:29:29.640
but they exist they exist okay more interesting things um
00:29:38.120
so does anybody know what this code
00:29:44.760
does gady is looking to embarrass himself even further it unfreezes the
00:29:55.159
Frozen that's true I is is true and this is how you might uh use
00:30:04.760
this I never needed it in my entire career uh which is 15 years in
00:30:10.840
Ruby but it exists optimizations after this ended up in in
00:30:17.799
Ruby yeah I'm very happy that we we are going this way like seriously like this
00:30:23.519
is going be proper it's good that this is happening in my managerial ears when
00:30:28.679
I don't give a sure uh I don't like this and by the way
00:30:36.919
there is a minus that is freezing strings if I remember correctly yeah but I will show you some
00:30:44.720
uh better things like uh an exercise in
00:30:50.640
inconsistency zero okay non zero NE false what
00:31:04.039
made in Japan my S uh some uh other funny examples about
00:31:13.039
Infinity just as consistent is one finite yes infinite
00:31:28.159
it gets even better uh I'm not sure how many people even know this but uh when
00:31:34.559
you use a her dog by default it behaves like a double quoted string litero so
00:31:41.120
things like interpolation and whatever are going to work there and U we can
00:31:47.600
illustrate this with an example this is of course the opening of
00:31:52.880
The Lord of the Rings and The inscription on the One Ring
00:31:58.880
I uh I would have written this in uh the language of the Orcs 20 years ago but
00:32:05.360
today old mature wise this is the example and the outcome is more or less
00:32:10.760
what You' expect uh we have the interpolation in Mordor okay nothing
00:32:17.240
shocking and you might be wondering is there a way to surpress the interpolation uh the way is slightly
00:32:24.760
weird you have to single quote um only the top
00:32:30.559
delimiter okay and the results are as you will expect them but here it gets
00:32:37.039
interesting if you do this you can actually have spaces in the delimiters
00:32:43.600
and you can actually have everything you want in the delimiters this is valid
00:32:54.000
code uh and uh with here dos uh there is something even less known you can Nest
00:33:02.320
those uh I learned about this from a ruby rubocop issue as usual so I
00:33:08.360
struggled to understand in the beginning what this code was supposed to do uh so
00:33:13.799
I illustrate it with an example and I know a value minus 5 but uh
00:33:25.279
o you can do this if you want I'm not going to hold this against you
00:33:31.919
but in reality I will okay so uh now the last 25 slides
00:33:39.480
and some of my favorite weird aspects in Ruby so how many ways uh are there to
00:33:47.480
invoke a Lambda show off hands for one for
00:33:53.440
two three okay four
00:34:05.679
five okay so um this is our Lambda and let's see um how many
00:34:12.520
different ways we can Co it I guess this is the tried and true
00:34:18.520
one yeah uh this is the modern sexy
00:34:26.040
way this is the old sexy way like geek CH
00:34:35.639
something wait wait for
00:34:43.839
it this can be only no there is
00:34:53.720
no was another weird one I don't make mistakes I don't make mistakes uh composition
00:35:00.720
maybe you're thinking of the composition was something I
00:35:06.720
remember yeah so tell me which method in Ruby's standard library has the most
00:35:13.280
aliases guesses size
00:35:24.640
no no
00:35:35.359
no I I think I'll have to give you a
00:35:40.880
hint so this is the original method which somebody
00:35:46.760
decided to as as member as key and as
00:35:55.119
key um and uh there are a few uh honorable mentions uh that have just two
00:36:03.200
aliases QP has also Q deck and Q shift Q push he has Q ank and Q give it to me
00:36:13.280
select filter find all um I don't
00:36:19.920
know I don't know it's too much and uh we are moving into the
00:36:27.240
Finish in C so do you know that uh if you put
00:36:32.640
something after the end thingy which I wouldn't call um I think it was a
00:36:39.079
compiler pragma or whatever this is actually going to be bound to the data
00:36:47.040
object yeah I believe and you're going to get this beautiful
00:36:53.680
output uh we can also we can also create in Ruby like um in
00:37:00.000
physics I remember how my professor in the Technical University of Sophia taught me that you cannot create energy
00:37:07.280
out of nothing you could only transform it I I showed this code to him
00:37:18.760
nothing I created an empty array an empty string some
00:37:25.160
numbers this guy knows and uh another uh another fun thing uh
00:37:34.240
you can do this in um in a slightly different and typically in the style of
00:37:39.599
Ruby inconsistent way because as you can see there is extended validation when
00:37:45.760
you're converting uh to an integer or a a float NE but for a race and hashes
00:37:53.280
this is cool I don't know I don't know
00:37:58.520
I will uh I will conclude this uh talk quoting um some python wisdom explicit
00:38:06.599
is better than implicit errors should never pass silently in the face of
00:38:12.000
ambiguity refuse the temptation to guess but this is Ruby we don't give a we
00:38:19.640
don't give a we want to keep Ruby weird it was a great pleasure to be here
