Re: Help me decide D or C
On Thursday, 1 August 2019 at 16:23:51 UTC, Alexandre wrote: On Thursday, 1 August 2019 at 15:42:08 UTC, a11e99z wrote: On Thursday, 1 August 2019 at 15:17:11 UTC, a11e99z wrote: Right now, job is not a good criteria for me. I work in a not related field and I doubt I would get any job working with CS. That would be great, but I doubt it anyway, so it is more a hobby thing. If penetrating a job segment-market is not a requirement, perhaps you would take pleasure in learning F*. It is a pure functional programming language based on logical-mathematical thought. It meant to be a replacement for Coq, a proof-assistant turned into general-purpose language. In my opinion, this kind of paradigm would fit quite well in the near-future RISCV technological and commercial market since their technical specifications have been feature-ready. Here is the official tutorial for F* language: https://www.fstar-lang.org/tutorial/ I hope this kind of project is the last step before entering the realm of quantum programming because it is time to embrace the change. Quantum mechanics are known since the 1930's, quantum physics since 50's, quantum information since 70's, quantum computation since 2000's. What are we waiting for quantum programming? Again the same and always pathological syndromes remain: "not invented here" and "it's if not broken, don't fix it." But don't fool yourself, D is not for beginners. Ali Çehreli is a very skilled programmer, ergo, he can't reason like a new/starting programmer anymore, regardless of his patience and kindness.
Re: Why does choose not work here
On 01.08.19 22:23, Matt wrote:
Version 4 does not work when PairedA.previous is null. I'd love to
understand why.
[...]
auto myFilter(R1, R2)(R1 a, R2 b)
{
import std.algorithm : filter, canFind;
return a.filter!(c => b.canFind(c));
}
struct A
{
uint[] starts, stops;
import std.range : ForwardRange, inputRangeObject;
import std.typecons : Tuple;
ForwardRange!(Tuple!(uint,uint)) intervalRange() @property
{
import std.algorithm : map;
import std.range : zip;
import std.typecons : tuple;
return zip(starts,stops).map!(a =>
tuple(a[0],a[1])).inputRangeObject;
}
}
struct PairedA
{
[...]
//version 4
auto uniqIntervals() @property
{
import std.range : choose;
import std.algorithm : filter, canFind;
return choose(previous is null,
primary.intervalRange,
primary.intervalRange
.myFilter(previous.intervalRange));
}
A primary;
A* previous;
}
`choose`'s parameters aren't lazy. So the second argument is evaluated
even when `previous is null`. That means `intervalRange` is called on a
null `previous`. And that fails, of course, because `intervalRange`
can't access `starts` or `stops` when `this` is null.
Why does choose not work here
I'm having some trouble with a "Program exited with code
-1073741819" error in some code I'm writing and I would
appreciate any help/insight.
The problem stems from some incompatibility between the Phobos
function "choose" and the template function "myFilter" which
returns a range. The code below is a simplified version of what
I'm trying to do. myFilter is a dummy/stand-in function that
highlights the error in my program (i.e. My function is not
simply a filter; it is much more complicated but unnecessary to
highlight my problem). In PairedA, sometimes previous will be
null. I need the uniqIntervals member function to do the right
thing depending on if previous is null or not. In an ideal
situation uniqIntervals would return a forward range where the
work would be done in a lazy fashion.
Version 1 works but is not lazy and does not use choose.
Version 2 works but requires converting the ranges to
ForwardRange classes, (I'd prefer to not use an unnecessary level
of indirection).
Version 3 uses the Phobos function filter which works inside
choose (but there is no Phobos function that can actual do why
myFilter stands in for. It's just interesting that the Phobos
function works where myFilter doesn't as they are both template
functions.
Version 4 does not work when PairedA.previous is null. I'd love
to understand why.
I'd also love to some one to show me what the best way to do this
would be. If version 2 is the best I can do, I'll live with it.
Thanks so much, the code is below:
auto myFilter(R1, R2)(R1 a, R2 b)
{
import std.algorithm : filter, canFind;
return a.filter!(c => b.canFind(c));
}
struct A
{
uint[] starts, stops;
import std.range : ForwardRange, inputRangeObject;
import std.typecons : Tuple;
ForwardRange!(Tuple!(uint,uint)) intervalRange() @property
{
import std.algorithm : map;
import std.range : zip;
import std.typecons : tuple;
return zip(starts,stops).map!(a =>
tuple(a[0],a[1])).inputRangeObject;
}
}
struct PairedA
{
//version 1
// auto uniqIntervals() @property
// {
// import std.array : array;
// if (previous is null) return primary.intervalRange.array;
// return primary.intervalRange
// .myFilter(previous.intervalRange).array;
// }
//version 2
// import std.range : ForwardRange, inputRangeObject;
// import std.typecons : Tuple;
// ForwardRange!(Tuple!(uint,uint)) uniqIntervals() @property
// {
// if (previous is null) return
primary.intervalRange.inputRangeObject;
// return primary.intervalRange
// .myFilter(previous.intervalRange).inputRangeObject;
// }
//version 3
// auto uniqIntervals() @property
// {
// import std.range : choose;
// import std.algorithm : filter, canFind;
// return choose(previous is null,
// primary.intervalRange,
// primary.intervalRange
// .filter!(a =>
previous.intervalRange.canFind(a)));
// }
//version 4
auto uniqIntervals() @property
{
import std.range : choose;
import std.algorithm : filter, canFind;
return choose(previous is null,
primary.intervalRange,
primary.intervalRange
.myFilter(previous.intervalRange));
}
A primary;
A* previous;
}
unittest
{
uint[] startsA = [1,100,1000,1];
uint[] stopsA = [2,200,2000,2];
uint[] startsB = [1,100];
uint[] stopsB = [2,200];
auto a1 = A(startsA, stopsA);
auto a2 = A(startsB, stopsB);
auto p = PairedA(a1, );
auto p2 = PairedA(a1, null);
import std.stdio : writeln;
writeln(p.uniqIntervals);//always works
writeln(p2.uniqIntervals);//Program exited with code -1073741819
for version 4
}
Re: Why does choose not work here
On Thursday, 1 August 2019 at 21:12:51 UTC, ag0aep6g wrote: `choose`'s parameters aren't lazy. So the second argument is evaluated even when `previous is null`. That means `intervalRange` is called on a null `previous`. And that fails, of course, because `intervalRange` can't access `starts` or `stops` when `this` is null. I forgot about lazy parameters. I tried changes myFilters second parameter to lazy, but that didn't help. So I guess I'm stuck with the "if" version using the ForwardRange interface (version 2)? Anyone have any other thoughts?
Re: Help me decide D or C
On Wednesday, 31 July 2019 at 22:30:52 UTC, Alexandre wrote: 1) Improve as a programmer 2) Have fun doing programs Thats it basically. I am planning to study all "free" time I have. I am doing basically this since last year. Try Basic. It has builtin graphics, seeing you program draw is quite fascinating.
Re: Help me decide D or C
On Wednesday, 31 July 2019 at 18:38:02 UTC, Alexandre wrote: Hi everyone, I would like an honest opinion. I have a beginner level (able to do very small programs) in a few languages such as python, go, C, guile(scheme) and common lisp. I want to pick a language and go deep with it and focus on only one for at least the next 2 years or so. Should I go for C and then when I become a better programmer change to D? Should I start with D right now? Here goes something that may help you. A multimedia tutorial in D with a lib called arsd. I am nearly done with the tutorial and it is now very complete, it now teaches how to use the arsd library to draw all sorts of stuff and to receive mouse and keyboard input. I think you will like it. If you use it and like it please let me know because I would be very happy to see my work being spread. Cheers. Here is the GitHub page: https://github.com/MuriloMir/arsd_multimedia_tutorial
Re: Help me decide D or C
On Thu, 2019-08-01 at 14:49 +, bachmeier via Digitalmars-d-learn wrote: […] > There's nothing wrong with Haskell if you want to take a deep > dive into pure functional programming. I personally find Haskell > to be more of a religion than a programming language. You can > learn the same perspective from functional-first languages like > Clojure, Scala, Ocaml, and F#. […] Whilst I agree that most "this is the one true programming language" people are quasi-religious, programming languages are not: Haskell is a just a lazy, pure functional programming language, some adherents show quasi-religious fervour, just as some adherents of C++, Java, C, Go, Rust, D, etc. do. I am not sure about F# (I do not know anything of it), but Clojure, Scala, and OCaml are very different from Haskell for various reasons, cf. lazy vs. eager, pure vs. impure. Haskell is a programming language worth learning for all programmers,along with Lisp, Prolog, and Erlang. I'll bet (but I have no experimental data, just a hypothesis) that any D programmer that knows Haskell writes better D than a D programmer who doesn't know Haskell. -- Russel. === Dr Russel Winder t: +44 20 7585 2200 41 Buckmaster Roadm: +44 7770 465 077 London SW11 1EN, UK w: www.russel.org.uk signature.asc Description: This is a digitally signed message part
Re: Help me decide D or C
I have spent the better part of 10 years with C, and it was my first serious language. I would say go with D if you just want to work on higher level projects and forego the low level details to an extent. C is very low level and very unforgiving. The inexperienced will run into things like segmentation faults or other memory errors until they understand how pointers and memory works. Also, while D has fewer available resources than C does, C is also an entirely different beast. The C standard library is very limited, only providing some very basic functionality. Advanced data structure implementations are not provided by it so you would be forced to either write your own or use a suitable third party library. Contrast this with C++ or D where such things are likely already provided by their standard libraries. In short, C is generally used to implement a foundation of sorts for higher level programs or other ventures where low level control is a requirement. For example, it is common to implement general purpose libraries for things like compression or encryption in C for performance reasons and also for reusable code. Libraries written in C can generally be used by any language that runs natively, usually through a binding or a translation of the library API.
Re: Help me decide D or C
On Thursday, 1 August 2019 at 15:42:08 UTC, a11e99z wrote: On Thursday, 1 August 2019 at 15:17:11 UTC, a11e99z wrote: [...] imo better choice is (with criteria to find best job) - Qt: C++ with any library that u need in one style - C#: web, graphics, mobiles, command tools with nice language. - Java/Kotlin: same as C# but in top-3. C# is top-5 with more comfort language than Java. Kotlin same comfort as C#, but JVM (Virtual Machine of Java and Kotlin) still does not support value types, that is sucks. - JavaScript/TypeScript: web-browser language with node.js that allows to program server side too. - You can try Python too. another dynamic language (as JavaScript). I don't like langs that based on space/tabs so I can not say anything about it. [...] Right now, job is not a good criteria for me. I work in a not related field and I doubt I would get any job working with CS. That would be great, but I doubt it anyway, so it is more a hobby thing.
Re: Help me decide D or C
On Wednesday, 31 July 2019 at 23:42:10 UTC, SashaGreat wrote: About Mike's book, you're talking about this one: https://www.amazon.com/Learning-D-Michael-Parker/dp/1783552484/ref=as_li_ss_tl?ie=UTF8=1448974911=8-1=learning+d=sl1=aldacron-20=d696b771c78030fc272e9b853986a708 Yep. It provides a lot of detail on a lot of topics. We're lucky to have a number of good books.
Re: Help me decide D or C
On Thursday, 1 August 2019 at 09:43:20 UTC, Kagamin wrote: On Wednesday, 31 July 2019 at 22:30:52 UTC, Alexandre wrote: 1) Improve as a programmer 2) Have fun doing programs Thats it basically. I am planning to study all "free" time I have. I am doing basically this since last year. Try Basic. It has builtin graphics, seeing you program draw is quite fascinating. What variant of Basic? Visual Basic? I think https://processing.org/ is the best if you want to "code with drawing"
Re: Help me decide D or C
On Thursday, 1 August 2019 at 09:43:20 UTC, Kagamin wrote: On Wednesday, 31 July 2019 at 22:30:52 UTC, Alexandre wrote: 1) Improve as a programmer 2) Have fun doing programs Thats it basically. I am planning to study all "free" time I have. I am doing basically this since last year. Try Basic. It has builtin graphics, seeing you program draw is quite fascinating. In that case I'd recommend EvalDraw: http://advsys.net/ken/download.htm with a C-like syntax with draw things while you type. Description: "A complete programming environment with built-in compiler, text editor, and functions to allow for quick prototyping. With Evaldraw, you can make graphs in any dimension (1D, 2D, 3D), animations, custom musical instruments, voxel models, and general purpose applications. I've included a lot of examples, so even if you're not a programmer, you can look at the demos" It was written by Ken Silverman (Creator of Build Engine - Duke Nukem 3D). Matheus.
Re: Example uses "volatile"; compiler says "undefined identifier volatile"
Thank you. I'll try that.
Re: Help me decide D or C
On Wednesday, 31 July 2019 at 18:38:02 UTC, Alexandre wrote: Hi everyone, I would like an honest opinion. I have a beginner level (able to do very small programs) in a few languages such as python, go, C, guile(scheme) and common lisp. I want to pick a language and go deep with it and focus on only one for at least the next 2 years or so. program bouncing ball on few languages and choose that more liked. learning language with numbers and strings only is boring. also you can program tasks from https://www.codingame.com/training/easy with dozen languages in web browser before install to local machine. some of them contains graphics https://www.codingame.com/ide/puzzle/power-of-thor-episode-1 when u run tests. read data from stdin, print result to stdout, and use stderr for debugging with diagnostics messages.
Re: Help me decide D or C
On Thursday, 1 August 2019 at 03:59:23 UTC, Bert wrote: But if you really want to learn to program I suggest you go with Haskell. You can do them all together too but Haskell is like learning Alien while D is learning German. There's nothing wrong with Haskell if you want to take a deep dive into pure functional programming. I personally find Haskell to be more of a religion than a programming language. You can learn the same perspective from functional-first languages like Clojure, Scala, Ocaml, and F#. The most common reason I hear for learning C is that you learn the foundation on which everything is built. And in one sense that's kind of true. It's portable assembly. The problem is that you don't learn much about programming, because C has so few features, and that limits you to (a) working on a narrow set of problems or (b) very slowly writing bug-ridden solutions to a wider group of problems. A big part of programming is learning about all the different ways to attack problems. You can go a long way with D, unlike C or Haskell.
Re: Help me decide D or C
On Thursday, 1 August 2019 at 15:17:11 UTC, a11e99z wrote: On Wednesday, 31 July 2019 at 18:38:02 UTC, Alexandre wrote: Hi everyone, I would like an honest opinion. I have a beginner level (able to do very small programs) in a few languages such as python, go, C, guile(scheme) and common lisp. I want to pick a language and go deep with it and focus on only one for at least the next 2 years or so. program bouncing ball on few languages and choose that more liked. learning language with numbers and strings only is boring. also you can program tasks from https://www.codingame.com/training/easy with dozen languages in web browser before install to local machine. some of them contains graphics https://www.codingame.com/ide/puzzle/power-of-thor-episode-1 when u run tests. read data from stdin, print result to stdout, and use stderr for debugging with diagnostics messages. imo better choice is (with criteria to find best job) - Qt: C++ with any library that u need in one style - C#: web, graphics, mobiles, command tools with nice language. - Java/Kotlin: same as C# but in top-3. C# is top-5 with more comfort language than Java. Kotlin same comfort as C#, but JVM (Virtual Machine of Java and Kotlin) still does not support value types, that is sucks. - JavaScript/TypeScript: web-browser language with node.js that allows to program server side too. - You can try Python too. another dynamic language (as JavaScript). I don't like langs that based on space/tabs so I can not say anything about it. C is too low level language. and many resources is not best criteria for it. (like people says "there's definitely something in the shit, a million flies can't be wrong"). D is stuck in some middle ages with subsistence economy, they still have stone tools but now they found iron/steel :)
