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Help me sort out the meaning of “{}” as a constructor argument

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Re: Help me sort out the meaning of “{}” as a constructor argument

#51

Post by bitL »

pjmlp wrote: post #45
bitL wrote: post #44

Earlier quoted context omitted.

The main advantage of C was that it allowed you to type stuff super fast comparing with Pascal ( {} instead of Begin .. End etc.) and had some very handy shortcuts for often used operations like ()?:, ++, --, += etc. Less verbose language, less need to type syntactic structures. You could basically keep the flow of what is in your mind with the progress on your keyboard and forget about typing it; you were simply ass…

Typing fast usually doesn't lead to working programs that solve what is actually the customer's problem. Software engineering isn't about "keeping the flow", rather about achieving the quality, deliverables and desired outcomes required by the users of the software.

It's what prepares you best as a young person to pass interviews at companies of your dreams or win ACM ICPC and similar competitions.

Re: Help me sort out the meaning of “{}” as a constructor argument

#52

Post by bitL »

premium-concern wrote: post #50
bitL wrote: post #40

Earlier quoted context omitted.

You'll go from bad to worse; Scala is to Java what C++ is to C; barely anyone understands all constructs in either language. You either know everything or nothing (i.e. you can't understand somebody else's code unless you enforce rules or know the complete language in detail).

I'd say this is blatant non-sense usually coming from people who lack any kind of experience in C++, Scala or both.

OK. Enjoy your ignorance then.

Re: Help me sort out the meaning of “{}” as a constructor argument

#53

Post by edblarney »

bitL wrote: post #40
_lbaq wrote: post #29

Earlier quoted context omitted.

Same here, I will look at Scala Native, like Scala, but instead of JVM as the target platform, its using LLVM

You'll go from bad to worse; Scala is to Java what C++ is to C; barely anyone understands all constructs in either language. You either know everything or nothing (i.e. you can't understand somebody else's code unless you enforce rules or know the complete language in detail).

I think this comment is fair, but could be misinterpreted.

Scala allows you to do the same thing in many different ways, and with operator overloading ... the approach you chose to coding defines almost a 'custom syntax' for a project.

Which makes it very hard to read sometimes - you have to infer the 'style' before you can get too far.

To be fair - that's a different kind of 'inconvenience' than C++ from C - but the comparison is pragmatically valid.

Re: Help me sort out the meaning of “{}” as a constructor argument

#54

Post by alyandon »

yoodenvranx wrote: post #18
Roboprog wrote: post #4

Earlier quoted context omitted.

Like "Wargames", the best way to win is not to play. Between moving from MS to POSIX environments in the 90s, and the "death" of Borland, this left me with few options other than another Faustian deal with Java-land, alas. I'm actually liking Javascript nowadays, though. Especially as more of an FP-capable language than an OOP-mandatory language.

I miss Delphi, it was awesome for rapid GUI development :(

You can check out the cross-platform OSS equivalent if you are feeling particularly nostalgic!

http://www.lazarus-ide.org/

Re: Help me sort out the meaning of “{}” as a constructor argument

#55

Post by seanwilson »

sqeaky wrote: post #49
seanwilson wrote: post #38

Earlier quoted context omitted.

> Then, one day, decades and several versions hence, you may find yourself now dealing with all of the warts that language has accrued over time. What languages are getting even close to being as bad as C++ in this respect though? Java, Python and JavaScript have been around for a while now for example and they seem more opinionated in a way that stops too many warts from appearing. C++ has undefined and compiler dep…

Most languages have Undefined and Implementation specific behavior. Few languages have so carefully specified their undefined behavior as C++ though.

Any examples? My experience is you will frequently be bitten by undefined behaviour in C++ if you don't know the rules well but this is very rare in other languages. It's rare you're going to get a segfault or the whole program crashing in languages like Python, Java and JavaScript.

Re: Help me sort out the meaning of “{}” as a constructor argument

#56

Post by nommm-nommm »

munificent wrote: post #33
seanwilson wrote: post #24

C++ FAQs are full of massively complex conundrums like this for problems you just don't get in other languages. I used to love learning all these highly specific C++ rules and playing language lawyer when I didn't know any better and thought it was a good use of learning time to become an expert. I've since moved on to languages that weren't full of problems like this that let you just get on with what you're meant t…

> I've since moved on to languages that weren't full of problems like this I think you mean aren't full of those problems yet . :) There's a lot of nasty corners in C++ but almost all of them are because it effectively has 40 years of wild success. (I say 40 because C++ inherits C's baggage and success.) It's totally reasonable to pick a younger language with fewer warts. Become an expert in it! Be productive! Ship l…

Java is over two decades old and one of the most widely used languages in the world. It has absolutely stood the test of time. While it does has its pain points its nowhere near as terrible as C++ and (in my opinion) is improving with new versions, and honestly, I think its a joy to program in though that might not be a "cool" thing to say. Whereas C++ is a chore to program in.

That's my opinion, maybe I'm just too used to high level programming to be "good" in C++ but my experience is C++ breaks the "principle of least astonishment" every single time I use it. For example, a simple operation like clearing a stringstream is... not straightforward.

...Or maybe I'm just not smart enough.

Re: Help me sort out the meaning of “{}” as a constructor argument

#57

Post by pjmlp »

bitL wrote: post #51
pjmlp wrote: post #45

Earlier quoted context omitted.

Typing fast usually doesn't lead to working programs that solve what is actually the customer's problem. Software engineering isn't about "keeping the flow", rather about achieving the quality, deliverables and desired outcomes required by the users of the software.

It's what prepares you best as a young person to pass interviews at companies of your dreams or win ACM ICPC and similar competitions.

None of the companies of my dreams was using C and "ACM ICPC and similar competitions" was done in Prolog.

Re: Help me sort out the meaning of “{}” as a constructor argument

#58

Post by pklausler »

shmageggy wrote: post #3
gpderetta wrote: post #2

The answer to the problem can be found in the comments, but not in a single place: X {{}}; will: for T = DefCtor call the initializer_list constructor with a single default constructed element. The outer brakets are for the initalizer list and the inner ones are for the DefCtor constructor. The brackets for T constructor itself are allowed to be elided. for T = NoDefCtor, the previous overload resolution is not valid…

My god c++ is atrocious.

Back in the 90's I was working on an operating system kernel that was written in C++. I had read up on the language and had done a lot of compiler work, so I was kind of a local tutor. I'll never forget my boss' reaction when he overheard me tell a coworker "look, if you want to expose your private parts here, you'll need to make a friend."

Re: Help me sort out the meaning of “{}” as a constructor argument

#59

Post by mvf0 »

seanwilson wrote: post #38
munificent wrote: post #33

Earlier quoted context omitted.

> I've since moved on to languages that weren't full of problems like this I think you mean aren't full of those problems yet . :) There's a lot of nasty corners in C++ but almost all of them are because it effectively has 40 years of wild success. (I say 40 because C++ inherits C's baggage and success.) It's totally reasonable to pick a younger language with fewer warts. Become an expert in it! Be productive! Ship l…

> Then, one day, decades and several versions hence, you may find yourself now dealing with all of the warts that language has accrued over time. What languages are getting even close to being as bad as C++ in this respect though? Java, Python and JavaScript have been around for a while now for example and they seem more opinionated in a way that stops too many warts from appearing. C++ has undefined and compiler dep…

I would argue that there are rabbit holes in Haskell that can lead to baroque terrors of syntax on par with the C++ horrors in the article. The difference between Haskell and C++ is that Haskell code always has a well defined meaning even if it is _insanely_ terse. There is no ambiguity like with C++.

Re: Help me sort out the meaning of “{}” as a constructor argument

#60

Post by seanwilson »

ksk wrote: post #47
seanwilson wrote: post #43

Earlier quoted context omitted.

Obviously this is very hard to quantify but for me the cognitive overload of being a good C++ is massively higher than for languages like Java, Python or JavaScript. C++ to me clearly has significantly more undefined behaviour, compiler specific behaviour and other quirks along with less safety nets (e.g. garbage collection, null pointer checks). Do you really find JavaScript, Ruby, Java and Ruby harder to master tha…

The blog post was about a possible bug in the syntax/standard itself. I pointed out that all languages have weird edge cases and buggy syntax. If you want to discuss programming languages in general then that is a totally separate discussion. C++ is not in the same class of languages as JS or Ruby, so why would you use them interchangeably? C++ is meant for low level system programming, when performance or size are c…

My comment started with "C++ FAQs are full of massively complex conundrums like this for problems you just don't get in other languages" so I was making a general comment prompted by the article.

> C++ is meant for low level system programming, when performance or size are constraints on the problem you're trying to solve. The problem domain itself entails a certain amount of care.

Agree with this but my view is you should avoid C++ at all costs if practical because of its productivity and bug risk impacts compared to other solutions. If low level is required though your options are limited.

> Also, JS and Ruby are indeed just as hard to master as C++.

We'll have to agree to disagree then because C++ is an order of magnitude more complex in my eyes. Code golf isn't a good metric to me as that's all about using obscure tricks to write as few characters as possible which isn't how you code normally. I would rather measure how easy it is to write code with minimal bugs and C++ gives you a million ways to shoot yourself in the foot.

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