Re: Idiomatic D code to avoid or detect devision by zero

2020-08-06 Thread Martin Tschierschke via Digitalmars-d-learn
On Monday, 3 August 2020 at 15:33:54 UTC, Dominikus Dittes 
Scherkl wrote:

[...]
For really long expressions you could also split it on multiple 
lines:


c = (b_expression == 0)
  ? (d_longer_expression)
  : (a_expression/b_expression);

+1 looks clean!



Re: Idiomatic D code to avoid or detect devision by zero

2020-08-03 Thread Martin Tschierschke via Digitalmars-d-learn
On Friday, 31 July 2020 at 14:18:15 UTC, Steven Schveighoffer 
wrote:

On 7/31/20 9:55 AM, Martin Tschierschke wrote:
What would be the idiomatic way to write a floating point 
division

occuring inside a loop and handle the case of division by zero.

c = a/b; // b might be zero sometimes, than set c to an other 
value (d).


(In the moment I check the divisor being zero or not, with an 
if-than-else structure,

but I find it ugly and so I ask here.)


c = b == 0 ? d : a/b;

I don't think a function would be shorter or clearer...

c = div(a, b, d);

Alternatively, you could use a type to effect the behavior you 
want.


-Steve


Thanks, for the hints.
I find the ? :  - expressions sometimes hard to reed, especially 
when a and b are not so  simple expressions.


I prefer putting additional bracket around:
c = (b_expression == 0) ? (d_longer_expression) : 
(a_expression/b_expression);


???


Re: Idiomatic D code to avoid or detect devision by zero

2020-08-03 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 31 July 2020 at 15:19:25 UTC, Andrea Fontana wrote:
On Friday, 31 July 2020 at 13:55:18 UTC, Martin Tschierschke 
wrote:
What would be the idiomatic way to write a floating point 
division

occuring inside a loop and handle the case of division by zero.

c = a/b; // b might be zero sometimes, than set c to an other 
value (d).


(In the moment I check the divisor being zero or not, with an 
if-than-else structure,

but I find it ugly and so I ask here.)


You should give a look at:
https://dlang.org/phobos/std_experimental_checkedint.html

You can try with checked!Throw and catch exceptions, for 
example.


Andrea


Thanks, I will look at it.


Idiomatic D code to avoid or detect devision by zero

2020-07-31 Thread Martin Tschierschke via Digitalmars-d-learn

What would be the idiomatic way to write a floating point division
occuring inside a loop and handle the case of division by zero.

c = a/b; // b might be zero sometimes, than set c to an other 
value (d).


(In the moment I check the divisor being zero or not, with an 
if-than-else structure,

but I find it ugly and so I ask here.)





Re: Compare string with German umlauts

2020-05-19 Thread Martin Tschierschke via Digitalmars-d-learn
On Monday, 18 May 2020 at 14:28:33 UTC, Steven Schveighoffer 
wrote:


What you need is to normalize the data for comparison: 
https://dlang.org/phobos/std_uni.html#normalize


For more reference: 
https://en.wikipedia.org/wiki/Combining_character


-Steve


I checked it again but could not reproduce the original error, it 
somehow seems that my compare string contained another error. But 
nevertheless good to know how to deal with encoding errors!




Re: Compare string with German umlauts

2020-05-19 Thread Martin Tschierschke via Digitalmars-d-learn
On Monday, 18 May 2020 at 14:28:33 UTC, Steven Schveighoffer 
wrote:

On 5/18/20 9:44 AM, Martin Tschierschke wrote:

[...]


using == on strings is going to compare the exact bits for 
equality. In unicode, things can be encoded differently to make 
the same grapheme. For example, ö is a code unit that is the o 
with a diaeresis (U+00F6). But you could encode it with 2 code 
points -- a standard o, and then an diaeresis combining 
character (U+006F, U+0308)


What you need is to normalize the data for comparison: 
https://dlang.org/phobos/std_uni.html#normalize

Thank you, I will check that.



Re: Compare string with German umlauts

2020-05-19 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 18 May 2020 at 14:22:31 UTC, WebFreak001 wrote:
[...]
It solved the problem, but what is the right way to use 
umlauts (encode them) inside the program?


Your code should have already worked like that, assuming your 
input file is a UTF-8 file. Check with an editor like Notepad++ 
or Visual Studio Code what the actual encoding of your text 
file is. In D all strings you specify in source are UTF-8 bytes 
in the end and a byte-by-byte comparison like with your line == 
"..." will cause it to fail if line is not UTF-8.

Thank you, I will check your hints!


Compare string with German umlauts

2020-05-18 Thread Martin Tschierschke via Digitalmars-d-learn

Hi,
I have to find a certain line in a file, with a text containing 
umlauts.


How do you do this?

The following was not working:

foreach(i,line; file){
 if(line=="My text with ö oe, ä ae or ü"){
   writeln("found it at line",i)
 }
}

I ended up using line.canFind("with part of the text without 
umlaut").


It solved the problem, but what is the right way to use umlauts 
(encode them) inside the program?




Deprecation message from phobos compiling a vibe.d app.

2020-01-30 Thread Martin Tschierschke via Digitalmars-d-learn
When building my small vibe.d app I am getting this messages 
twice:


/usr/include/dmd/phobos/std/range/primitives.d(174,38): 
Deprecation: alias byKeyValue this is deprecated - Iterate over 
.byKeyValue instead.
/usr/include/dmd/phobos/std/range/primitives.d(176,27): 
Deprecation: alias byKeyValue this is deprecated - Iterate over 
.byKeyValue instead.
/usr/include/dmd/phobos/std/range/primitives.d(174,38): 
Deprecation: alias byKeyValue this is deprecated - Iterate over 
.byKeyValue instead.
/usr/include/dmd/phobos/std/range/primitives.d(176,27): 
Deprecation: alias byKeyValue this is deprecated - Iterate over 
.byKeyValue instead.


Unfortunately I don't know what is triggering this and what to do 
about.

The build is working, so it is more a question of elegance.


Re: Meta question - what about moving the D - Learn Forum to a seperate StackExchange platform?

2019-10-18 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 18 October 2019 at 13:38:11 UTC, Ron Tarrant wrote:
On Friday, 18 October 2019 at 07:35:21 UTC, Martin Tschierschke 
wrote:
I very often end with a solution found on one of the 
StackExchange forums like > StackOverflow or AskUbuntu etc.


I have found that StackExchange does often have answers, but I 
can't say I like asking questions on there, especially if the 
question is almost-the-same-but-not-the-same as a question 
asked earlier. In cases like this, I've been told that the 
previous answer applies to my question, even when it doesn't.


In one instance, a moderator closed my question without reading 
the details in order to find out that, no, it's not the same 
question at all... and then refuse to reopen the question when 
I point this out.


So, although I'll continue to use StackExchange as an 
historical resource, I would rather not depend on it for 
getting answers to new questions.


This is why I am for an own D Learn Forum, the process is 
(partly) described here:

https://meta.stackexchange.com/questions/76974/how-can-i-propose-a-new-site

The moderators of this should come from this forum community, if 
this can not be achieved, I am against a move, too.


Re: Meta question - what about moving the D - Learn Forum to a seperate StackExchange platform?

2019-10-18 Thread Martin Tschierschke via Digitalmars-d-learn
On Friday, 18 October 2019 at 12:41:53 UTC, Paolo Invernizzi 
wrote:

On Friday, 18 October 2019 at 11:45:33 UTC, Seb wrote:
On Friday, 18 October 2019 at 10:55:59 UTC, Martin 
Tschierschke wrote:

[...]


In the state of the D survey, there were more people in favor 
of StackOverflow than D.learn, but to be fair the majority 
voted for "I don't care"


https://rawgit.com/wilzbach/state-of-d/master/report.html


Maybe it's possible to simply add an up/down vote functionality 
to the forum only, just keeping the compatibility with the 
newsgroup ...


It's a win/win solution!

+1
It may help in the DIP discussions, too!

You can just see if an argument for or against a change, is 
accepted by the majority of thread readers or not. And you can 
highlight those up-voted arguments to get an better impression 
about the outcome of the discussion in total.


Re: Meta question - what about moving the D - Learn Forum to a seperate StackExchange platform?

2019-10-18 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 18 October 2019 at 12:51:35 UTC, bachmeier wrote:
On Friday, 18 October 2019 at 07:35:21 UTC, Martin Tschierschke 
wrote:
If I search for what ever, not related to D, I very often end 
with a solution
found on one of the StackExchange forums like StackOverflow or 
AskUbuntu etc.


The main advantage is, that all answers can be classified 
(up/down voted, moderated etc.)
This is much better than finding something in the D-Learn 
Forum where it is difficult to see,
if several answers are given are they still valid, especially 
if they are some years old.


I know that this was asked in the D survey and I think it 
should be on the table again.


If we unite for this idea, it should be possible to start an 
own "DExchange" sub platform.


Best regards mt.


You can already ask questions on SO. What you are proposing is 
to close this forum, require registration to ask a question, 
and let JavaScript developers close questions and treat new 
users rudely. That doesn't seem like a good idea. The fact that 
most questions get asked here rather than on SO now suggests 
that there isn't much demand for SO.


I am not for moving just to StackOverflow, but to make an own 
"DExchange" / "AskD" or what ever named learn platform with and 
inside the StackExchange [1] technology. This should keep D users 
together and would avoid mixing with other languages. But I am 
not sure if this is really achievable for us.


[1] https://stackexchange.com/sites#





Re: Meta question - what about moving the D - Learn Forum to a seperate StackExchange platform?

2019-10-18 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 18 October 2019 at 10:23:28 UTC, jmh530 wrote:
On Friday, 18 October 2019 at 07:35:21 UTC, Martin Tschierschke 
wrote:

[snip]


I think this is something that's been proposed before, but most 
people are happy with just asking a question here and usually 
people are pretty good about helping out with answers when 
possible.


Yes, it works as it is, but it is not the best solution to share 
know how.


And if I just think: Hey, your answer is good, in the mailinglist 
/ forum / newsgroup setup it is impossible to easily vote for it 
and get a count of this votes.


I think it is possible to extended the web front end of the forum 
in this direction and automatically map an '+1' or '-1' comment 
(in a single line) to a counter which will be displayed beside 
the commented post. But this is reinventing the wheel...


I am just sad, that many very good questions and answers given in 
the forum are not so easy to find as they should.


Meta question - what about moving the D - Learn Forum to a seperate StackExchange platform?

2019-10-18 Thread Martin Tschierschke via Digitalmars-d-learn
If I search for what ever, not related to D, I very often end 
with a solution
found on one of the StackExchange forums like StackOverflow or 
AskUbuntu etc.


The main advantage is, that all answers can be classified 
(up/down voted, moderated etc.)
This is much better than finding something in the D-Learn Forum 
where it is difficult to see,
if several answers are given are they still valid, especially if 
they are some years old.


I know that this was asked in the D survey and I think it should 
be on the table again.


If we unite for this idea, it should be possible to start an own 
"DExchange" sub platform.


Best regards mt.


Re: DUB and ddoc - howto?

2019-06-28 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 28 June 2019 at 13:03:17 UTC, Daniel Kozak wrote:

Did you try dub build --help?


Oh, thank you! I just looked at dub --help | grep -i doc ... and 
several other places...




DUB and ddoc - howto?

2019-06-28 Thread Martin Tschierschke via Digitalmars-d-learn
A very simple question, is there an example how to generate 
documentation with dub?

(like dmd -D)

My internet search was not successful.



Re: [vibe-d/dub] Lin

2018-09-10 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 7 September 2018 at 16:37:18 UTC, MamoKupe wrote:

On Friday, 7 September 2018 at 16:20:40 UTC, MamoKupe wrote:

marcinan@marcinan-PC ~/Pulpit/d $ dub init bibe
Package recipe format (sdl/json) [json]: d
Invalid format, "d", enter either "sdl" or "json".
Package recipe format (sdl/json) [json]:
Name [bibe]:
Description [A minimal D application.]:
Author name [Marcin]:
License [proprietary]:
Copyright string [Copyright © 2018, Marcin]:
Add dependency (leave empty to skip) []: vibe-d
Added dependency vibe-d ~>0.8.4



/usr/bin/ld: cannot find -lssl
/usr/bin/ld: cannot find -lcrypto
collect2: error: ld returned 1 exit status
Error: linker exited with status 1
/usr/bin/dmd failed with exit code 1.

On linux Mint with DUB version 1.11.0, built on Sep  1 2018



sudo apt-get install libssl-dev

Solved linking problem for now.


Yes, but this should be detected by dub before compilation as a 
missing dependency not after.
Someone told, that is is possible by adding the right params to 
dub.sdl/.json.
As an traditional error most "lets try vibe.d"-people see, I 
would like to ask for changing this.


Regards mt.


Re: Determine if CTFE or RT

2018-06-25 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 25 June 2018 at 08:05:53 UTC, Mr.Bingo wrote:

On Monday, 25 June 2018 at 07:02:24 UTC, Jonathan M Davis wrote:
On Monday, June 25, 2018 05:47:30 Mr.Bingo via 
Digitalmars-d-learn wrote:
The problem then, if D can't arbitrarily use ctfe, means that 
there should be a way to force ctfe optionally!


If you want to use CTFE, then give an enum the value of the 
expression you want calculated. If you want to do it in place, 
then use a template such as


template ctfe(alias exp)
{
enum ctfe = exp;
}

so that you get stuff like func(ctfe!(foo(42))). I would be 
extremely surprised if the compiler is ever changed to just 
try CTFE just in case it will work as an optimization. That 
would make it harder for the programmer to understand what's 
going on, and it would balloon compilation times. If you want 
to write up a DIP on the topic and argue for rules on how CTFE 
could and should function with the compiler deciding to try 
CTFE on some basis rather than it only being done when it must 
be done, then you're free to do so.


https://github.com/dlang/DIPs

But I expect that you will be sorely disappointed if you ever 
expect the compiler to start doing CTFE as an optimization. 
It's trivial to trigger it explicitly on your own, and 
compilation time is valued far too much to waste it on 
attempting CTFE when in the vast majority of cases, it's going 
to fail. And it's worked quite well thus far to have it work 
only cases when it's actually needed - especially with how 
easy it is to make arbitrary code run during CTFE simply by 
doing something like using an enum.


- Jonathan M Davis


You still don't get it!

It is not trivial! It is impossible to trigger it! You are 
focused far too much on the optimization side when it is only 
an application that takes advantage of the ability for rtfe to 
become ctfe when told, if it is possible.


I don't know how to make this any simpler, sorry... I guess 
we'll end it here.


I am not sure that I understood it right, but there is a way to 
detect the status of a parameter:


My question was different, but I wished to get a ctRegex! or 
regex used depending on the expression:


 import std.regex:replaceAll,ctRegex,regex;

 auto reg(alias var)(){
   static if (__traits(compiles, {enum ctfeFmt = var;}) ){
// "Promotion" to compile time value
enum ctfeReg =  var ;
pragma(msg, "ctRegex used");
return(ctRegex!ctfeReg);

   }else{
return(regex(var));
pragma(msg,"regex used");
}
   }
}
So now I can always use reg!("") and let the compiler decide.

To speed up compilation I made an additional switch, that when 
using DMD (for development)

alway the runtime version is used.

The trick is to use the alias var in the declaration and check if 
it can be assigned to enum.
The only thing is now, that you now always use the !() compile 
time parameter to call the function. Even, when in the end is 
translated to an runtime call.


reg!("") and not reg("...").







Re: Convert a huge SQL file to CSV

2018-06-01 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 1 June 2018 at 09:49:23 UTC, biocyberman wrote:
I need to convert a compressed 17GB SQL dump to CSV. A workable 
solution is to create a temporary mysql database, import the 
dump, query by python, and export. But i wonder if there is 
something someway in D to parse the SQL file directly and query 
and export the data. I imagine this will envolve both parsing 
and querying because the data is stored in several tables. I am 
in the process of downloading the dump now so I can’t give 
excerpt of the data.


You don't need python:
https://michaelrigart.be/export-directly-mysql-csv/

SELECT field1, field2
FROM table1
INTO OUTFILE '/path/to/file.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
FIELDS ESCAPED BY '\'
LINES TERMINATED BY '\n';

Most important:

INTO OUTFILE : here you state the path where you want MySQL to 
store the CSV file. Keep in mind that the path needs to be 
writeable for the MySQL user


You can write a parser for SQL in D, but even if the import into 
mysql would take some time, it's only compute time and not yours.



Regards mt.


Re: Why The D Style constants are written in camelCase?

2018-05-15 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 9 May 2018 at 11:52:11 UTC, Jonathan M Davis wrote:
On Wednesday, May 09, 2018 09:38:14 BoQsc via 
Digitalmars-d-learn wrote:

[...]


Every language makes its own choices with regards to how it 
goes about things, some of which are purely subjective.

[...]

- Jonathan M Davis


Just a thank you, for your patient and well written explanations!


Re: Parse .eml files

2018-04-12 Thread Martin Tschierschke via Digitalmars-d-learn

On Thursday, 12 April 2018 at 00:00:04 UTC, bachmeier wrote:
On Wednesday, 11 April 2018 at 15:20:08 UTC, Martin 
Tschierschke wrote:


My question in the moment is, how do I invoke Thunderbird to 
display a certain single mail (or maildir) file?
How do I use Thunderbird as the client, to show, to answer or 
to forward these mails.
An alternative would be to use a browser based mailer? 
Handling all attachments is an other purpose.


Can you use executeShell and call Thunderbird from the command 
line? Something like


executeShell("thunderbird -compose \"subject='My Christmas 
Gift',body='Please send me a new car',to='sa...@claus.net'")


http://kb.mozillazine.org/Command_line_arguments_%28Thunderbird%29


Thank you, especially for the Link!
There I saw, that attachment with a local file is possible. So It 
should be possible to invoke Thunderbird with the extracted 
elements of an existing email.




Re: Parse .eml files

2018-04-11 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 11 April 2018 at 02:37:39 UTC, bachmeier wrote:

On Monday, 9 April 2018 at 19:17:20 UTC, Adam D. Ruppe wrote:

[...]

I had a chance to try this out and it worked without a problem. 
I did have to download color.d in addition to the other 
dependencies you listed. In the event that Google brings 
someone here, this is a complete working program:


import std.file, std.stdio, std.string;
import arsd.email;

void main(string[] args) {
  string[] f = std.file.readText(args[1]).splitLines();
  auto em = new IncomingEmailMessage(f);
  writeln("From: ", em.from);
  writeln("To: ", em.to);
  writeln("Subject: ", em.subject);
  writeln(em.textMessageBody);
}

Compile with

dmd *.d -ofreademail

And run

./reademail 'email message.eml'


Very cool, I was looking for something similar, thank you both 
for sharing!


My goal is to store mails in a mysql table with fulltext index, 
connected to a existing old crm solution via the email address as 
a foreign key.


My question in the moment is, how do I invoke Thunderbird to 
display a certain single mail (or maildir) file?
How do I use Thunderbird as the client, to show, to answer or to 
forward these mails.
An alternative would be to use a browser based mailer? Handling 
all attachments is an other purpose.





Re: #import mapi.h

2018-03-23 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 23 March 2018 at 01:12:58 UTC, Mike Parker wrote:
On Thursday, 22 March 2018 at 21:45:40 UTC, Martin Tschierschke 
wrote:

On Thursday, 22 March 2018 at 17:42:46 UTC, Paul Backus wrote:
On Wednesday, 21 March 2018 at 16:22:45 UTC, Martin 
Tschierschke wrote:
Is there an step by step introduction how to convert a C 
header of an external lib into the right extern(C){} block?


In addition to what others have said, I found the following 
article on the D Wiki useful:


https://wiki.dlang.org/D_binding_for_C


Thank you, this one is very good!


If you have Learning D, chapter 9 is all about interface D with 
C.


I will look at it! I have seen your hint already, you have 
mentioned it in the beginning of your blogpost. The discussion in 
an other thread [1] about direct integration of an C/C++ 
preprocessor into the D complier(s) is very interesting, I think 
this will push the adoption of the language, because you just can 
start immediately to use D as a replacement for C or C++. It is 
very fascinating to see how D is evolving all the time. Now I 
hope that with the survey and more donations the D Foundation get 
the ability to push this even more.


[1] 
https://forum.dlang.org/post/hvanbsyrydsxpizlt...@forum.dlang.org




Re: #import mapi.h

2018-03-22 Thread Martin Tschierschke via Digitalmars-d-learn

On Thursday, 22 March 2018 at 17:42:46 UTC, Paul Backus wrote:
On Wednesday, 21 March 2018 at 16:22:45 UTC, Martin 
Tschierschke wrote:
Is there an step by step introduction how to convert a C 
header of an external lib into the right extern(C){} block?


In addition to what others have said, I found the following 
article on the D Wiki useful:


https://wiki.dlang.org/D_binding_for_C


Thank you, this one is very good!



Re: #import mapi.h

2018-03-22 Thread Martin Tschierschke via Digitalmars-d-learn
On Thursday, 22 March 2018 at 12:53:23 UTC, Martin Tschierschke 
wrote:

On Wednesday, 21 March 2018 at 17:12:07 UTC, Timoses wrote:

[...]

I got it, my first mini test with C bindings!
Important missing at first: (stderr)

import core.stdc.stdio : stderr, FILE;
and use of toStringz inside:  mapi_query(dbh, toStringz(q) )

After installing monetdb and starting the server with:
https://www.monetdb.org/Documentation/UserGuide/Tutorial

My minimal version of the example compiled with
dmd app.d -I /usr/local/lib/libmapi.so

(My dub.json is still incomplete so the linking failed.)

Here is the code: (only the minimum of mapi.h is icluded!)

```
 std.stdio;
import std.string;

/* interfacing winth monetdb #include mapi.h */
/* minimum to run code of example at: 
https://www.monetdb.org/Documentation/Manuals/SQLreference/Programming/MAPI */

import core.stdc.stdio : stderr,FILE;
import core.stdc.stdlib;

struct MapiStruct;
alias Mapi = MapiStruct*;

struct MapiStatement;
alias MapiHdl = MapiStatement*;

enum MOK = 0 ;

alias MapiMsg = int;

extern(System){
Mapi mapi_connect(const char* host, int port, const char* 
username, const char* password, const char* lang, const char* 
dbname);

MapiHdl mapi_query(Mapi mid, const char *cmd);
int mapi_fetch_row(MapiHdl hdl);
char *mapi_fetch_field(MapiHdl hdl, int fnr);
MapiMsg mapi_error(Mapi mid);
MapiMsg mapi_explain(Mapi mid, FILE* fd);
MapiMsg mapi_destroy(Mapi mid);
MapiMsg mapi_close_handle(MapiHdl hdl);
MapiMsg mapi_explain_result(MapiHdl hdl, FILE* fd);
MapiMsg mapi_next_result(MapiHdl hdl);
MapiMsg mapi_explain_query(MapiHdl hdl, FILE* fd);
char *mapi_result_error(MapiHdl hdl);
}


void die(Mapi dbh, MapiHdl hdl) {
  if (hdl != null) {
mapi_explain_query(hdl, stderr);
do {
  if (mapi_result_error(hdl) != null)
mapi_explain_result(hdl, stderr);
} while (mapi_next_result(hdl) == 1);
mapi_close_handle(hdl);
mapi_destroy(dbh);
  } else if (dbh != null) {
mapi_explain(dbh, stderr);
mapi_destroy(dbh);
  } else {
fprintf(stderr, "command failed\n");
  }
  exit(-1);
}


MapiHdl query(Mapi dbh, string q) {
  MapiHdl ret = null;
  if ((ret = mapi_query(dbh, toStringz(q) )) == null || 
mapi_error(dbh) != MOK)

die(dbh, ret);
  return(ret);
}

void update(Mapi dbh, string q) {
  MapiHdl ret = query(dbh, q);
  if (mapi_close_handle(ret) != MOK)
die(dbh, ret);
}

void main()
{

auto  dbh = mapi_connect("localhost", 5, "monetdb", 
"monetdb", "sql", "voc");

  writeln("DB-connect");
  update(dbh, "CREATE TABLE emp (name VARCHAR(20), age INT)");
  writeln("create");
  update(dbh, "INSERT INTO emp VALUES ('John', 23)");
  update(dbh, "INSERT INTO emp VALUES ('Mary', 22)");
auto hdl = query(dbh, "SELECT * FROM emp");
  while (mapi_fetch_row(hdl)) {
auto name = mapi_fetch_field(hdl, 0);
auto age = mapi_fetch_field(hdl, 1);
printf("%s is %s\n", name, age);
  }
}
```

Will try to make a complete binding available later...


Re: #import mapi.h

2018-03-22 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 21 March 2018 at 17:12:07 UTC, Timoses wrote:
On Wednesday, 21 March 2018 at 16:22:45 UTC, Martin 
Tschierschke wrote:
Is there an step by step introduction how to convert a C 
header of an external lib into the right extern(C){} block?


A blog post or tutorial, or chapter in a D book? (I have those 
from Packt Publishing)


While googling I found this:
https://dlang.org/blog/2017/12/05/interfacing-d-with-c-getting-started/

Haven't read it yet, but might give you some more insight.

For automatic conversion I stumbled across Dstep which I so far 
like a lot:

https://github.com/jacob-carlborg/dstep


Thank you! I will have a look at both, an Mike Parker is pointing 
to his book, too,
so now together with the post  from "nkm1" I should be able to 
make it!


@ketmar, I learned C but the counter of years from that time was 
stored in a nibble and so I got an overflow...error :-)


Re: #import mapi.h

2018-03-22 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 21 March 2018 at 18:42:43 UTC, nkm1 wrote:
On Wednesday, 21 March 2018 at 16:22:45 UTC, Martin 
Tschierschke wrote:

[...]


The easiest thing to do is to write a wrapper in C. The wrapper 
will include all necessary headers and provide some easy to use 
functions that you can call from D. Of course, you'll need to 
use a C compiler to compile it.
Anyway, this header looks very straightforwar, no particular 
tricks with the preprocessor. It should be something like this 
(untested, obviously):


[...]

Thank you!
Especially this was a missing link:

struct MapiStruct;
alias Mapi = MapiStruct*;


#import mapi.h

2018-03-21 Thread Martin Tschierschke via Digitalmars-d-learn
Is there an step by step introduction how to convert a C header 
of an external lib into the right extern(C){} block?


A blog post or tutorial, or chapter in a D book? (I have those 
from Packt Publishing)


(Especially I am trying to get this used with D:
Montetdb C-API 
https://www.monetdb.org/Documentation/Manuals/SQLreference/Programming/MAPI
With: 
https://github.com/snaga/monetdb/blob/master/clients/mapilib/mapi.h)


The page: https://dlang.org/spec/interfaceToC.html is known, but 
not detailed enough for me.


Re: What's the proper way to add a local file dependence to dub?

2018-03-12 Thread Martin Tschierschke via Digitalmars-d-learn
On Monday, 12 March 2018 at 09:38:41 UTC, Martin Tschierschke 
wrote:

On Sunday, 4 March 2018 at 16:46:56 UTC, Marc wrote:

[...]


I did it this sway:
the part of dub.json:
"dependencies": {


[...]

"mylib":{
"versions": "~master",
"path": "/home/mt/d/mylib"
}
},

In spite of using a version directly after the used lib,
you give two parameters

  "versions" : "~master"

and

  "path": "/path_to_your_lib/"

Works well.

And in ...mylib/dub.json
you just add:

"targetType": "library",

on the top-level, and place your dir.d in ...mylib/source/



Re: What's the proper way to add a local file dependence to dub?

2018-03-12 Thread Martin Tschierschke via Digitalmars-d-learn

On Sunday, 4 March 2018 at 16:46:56 UTC, Marc wrote:

then copy it to sources folder?

let's say I have a small library folder at C:\mylibrary\D where 
I want to use dir.d from it. How do I add that file dependence 
to dub? But I do not want to that file be passed directly to 
dmd, I want to that file be copied to application's source 
folder (so it's easy to distribuite, with the dependences 
together as possible) then compiled. So, what I want to some 
extension is dub work with loca files.
Is this possible to do solely with dub? I know I can easily 
write a script to run before dub which copies the dependence 
files from C:\mylibrary to application's source but I'm looking 
for a more elegant
 approach as possible; I'm afraid of rewriting a makefile-like 
soon (I find cmake/make/makefiles just ugly).


I did it this sway:
the part of dub.json:
"dependencies": {

"diet-ng": "~>1.4",
"vibe-d:tls": "~>0.8.0",
"vibe-d:http": "~>0.8",
"mysql-d": "~>0.3",
"mylib":{
"versions": "~master",
"path": "/home/mt/d/mylib"
}
},

In spite of using a version directly after the used lib,
you give two parameters

  "versions" : "~master"

and

  "path": "/path_to_your_lib/"

Works well.




Re: dmd-2.078.2 problems with Ubuntu 17.10 32Bit

2018-02-17 Thread Martin Tschierschke via Digitalmars-d-learn
On Wednesday, 14 February 2018 at 11:23:48 UTC, Andrea Fontana 
wrote:
On Wednesday, 14 February 2018 at 11:16:25 UTC, Martin 
Tschierschke wrote:

Ok, good to know!
I started with 16.04 and made the initial mistake to take the 
32 Bit version,

do you use 32 or 64 Bit?


64bit of course!

Andrea


After this info, I made the step to change to Ubuntu 17.10 64 Bit.
And - it works!

But the installation via apt-get is not working without the steps 
already mentioned in the post before! (s/http/https/  and 
manually import of the public key)


This (from https://dlang.org/download.html) is outdated for 17.10.

sudo wget 
http://master.dl.sourceforge.net/project/d-apt/files/d-apt.list 
-O /etc/apt/sources.list.d/d-apt.list
sudo apt-get update && sudo apt-get -y --allow-unauthenticated 
install --reinstall d-apt-keyring

sudo apt-get update && sudo apt-get install dmd-compiler dub




Re: rdmd main.d leads to Segmentation fault

2018-02-14 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 14 February 2018 at 10:28:51 UTC, Kagamin wrote:
On Tuesday, 13 February 2018 at 06:53:46 UTC, Martin 
Tschierschke wrote:
I am unfamiliar with debugging (gdb etc.) so any hint would be 
appreciated!


https://issues.dlang.org/show_bug.cgi?id=18350 - maybe adjust 
bug severity.

I added a comment and increased prio, OK to do it like this?
I may post my gdb results in the MET evening later, should I?



Re: dmd-2.078.2 problems with Ubuntu 17.10 32Bit

2018-02-14 Thread Martin Tschierschke via Digitalmars-d-learn
On Wednesday, 14 February 2018 at 10:57:47 UTC, Andrea Fontana 
wrote:
On Tuesday, 13 February 2018 at 22:21:18 UTC, Martin 
Tschierschke wrote:
I will downgrade to 16.04., the dist-upgrade to 17.10 was a 
mistake, resulting in problems with startx and newer kernels 
so I have to use 4.10.


In my experience dist-upgrade are long and messy :)
Usually I create a partition on disk; install a fresh (K)ubuntu 
on that partition; move data / config from old partition to 
new; delete (or backup) old partition.


I have both kubuntu 17.04 and 17.10 and dmd works fine.

Andrea

Ok, good to know!
I started with 16.04 and made the initial mistake to take the 32 
Bit version,

do you use 32 or 64 Bit?



Re: dmd-2.078.2 problems with Ubuntu 17.10 32Bit

2018-02-13 Thread Martin Tschierschke via Digitalmars-d-learn

On Tuesday, 13 February 2018 at 21:25:44 UTC, Jordi Sayol wrote:
El 13/02/18 a les 08:03, Martin Tschierschke via 
Digitalmars-d-learn ha escrit:

On Monday, 12 February 2018 at 21:18:01 UTC, Jordi Sayol wrote:
El 12/02/18 a les 21:56, Martin Tschierschke via 
Digitalmars-d-learn ha escrit:
I just started to play around with D again on my notebook at 
home and realized,

that I have a broken installation.
Even the minimal D "hello world" throws an error at 
execution.
Speicherzugriffsfehler (Speicherabzug geschrieben) aka. core 
dump


Compiling with ldc2 still works.
Any hint?





d-apt <http://d-apt.sourceforge.net/>


After setting ulimit -c unlimited to get the core dumped, I 
took a look with gdb, to find a hint, now realizing, that it 
is probably the same problem as here: 
https://forum.dlang.org/thread/jjaynewwdsyntyehv...@forum.dlang.org?page=1




A fresh install from d-apt on Ubuntu 16.04 32-bit, and 
everything worked fine.




I tried a lot, there is special bug new on ubuntu 17.10 in
/etc/apt/sources.list.d/d-apt.list

!!! I had to change http://... to https://


Before that I imported the key with
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 
EBCF975E5BA24D5E


I am not sure if this was necessary, probably not.

Than I was able to call

sudo apt-get update && sudo apt-get -y --allow-unauthenticated 
install --reinstall d-apt-keyring && sudo apt-get update


and install with

sudo apt-get install dmd-compiler dub

But unfortunately still the same core dump.

Is there anyone using Ubuntu 17.10 32 Bit?

I will downgrade to 16.04., the dist-upgrade to 17.10 was a 
mistake, resulting in problems with startx and newer kernels so I 
have to use 4.10.




Re: dmd-2.078.2 problems with Ubuntu 17.10 32Bit

2018-02-12 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 12 February 2018 at 21:18:01 UTC, Jordi Sayol wrote:
El 12/02/18 a les 21:56, Martin Tschierschke via 
Digitalmars-d-learn ha escrit:
I just started to play around with D again on my notebook at 
home and realized,

that I have a broken installation.
Even the minimal D "hello world" throws an error at execution.
Speicherzugriffsfehler (Speicherabzug geschrieben) aka. core 
dump


Compiling with ldc2 still works.
Any hint?





d-apt <http://d-apt.sourceforge.net/>


After setting ulimit -c unlimited to get the core dumped, I took 
a look with gdb,
to find a hint, now realizing, that it is probably the same 
problem as here:

https://forum.dlang.org/thread/jjaynewwdsyntyehv...@forum.dlang.org?page=1


Re: rdmd main.d leads to Segmentation fault

2018-02-12 Thread Martin Tschierschke via Digitalmars-d-learn

On Sunday, 4 February 2018 at 11:50:05 UTC, Timoses wrote:

On Thursday, 1 February 2018 at 09:01:34 UTC, Kagamin wrote:

On Wednesday, 31 January 2018 at 16:59:15 UTC, Timoses wrote:

And I would need to do what about it?

Sorry, I'm not familiar with assembly code stuff in detail.


You can try to see if it works on another distro or version.


It does work on debian jessie. Stretch failed..


It looks like I have the same issue, I got:
gdb hiworld core
Core was generated by `./hiworld'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x800fbf73 in _d_dso_registry ()

ldc2 is working.

My system: Ubuntu 17.10 32 Bit
4.10.0-37-generic #41-Ubuntu SMP Fri Oct 6 20:20:00 UTC 2017 i686 
i686 i686 GNU/Linux


(No problems on our office system Ubuntu 16.04 64Bit, too)

I tried older DMD (from 2017 and 2016!), because I already used 
DMD on this system, but I got the same same effect.


I am unfamiliar with debugging (gdb etc.) so any hint would be 
appreciated!


Re: dmd-2.078.2 problems with Ubuntu 17.10 32Bit

2018-02-12 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 12 February 2018 at 21:08:30 UTC, Seb wrote:
On Monday, 12 February 2018 at 20:56:11 UTC, Martin 
Tschierschke wrote:
I just started to play around with D again on my notebook at 
home and realized,

that I have a broken installation.
Even the minimal D "hello world" throws an error at execution.
Speicherzugriffsfehler (Speicherabzug geschrieben) aka. core 
dump


Compiling with ldc2 still works.
Any hint?


How did you install DMD? It's probably related to this.
I recommend using the official releases:

curl https://dlang.org/install.sh | bash -s dmd


See also: https://dlang.org/install.html


I did so, and after that, I tried to install via dpkg -i *.deb, 
than I tried to use an older version... without success, maybe I 
first have to clean up? But how to deinstall best?


dmd-2.078.2 problems with Ubuntu 17.10 32Bit

2018-02-12 Thread Martin Tschierschke via Digitalmars-d-learn
I just started to play around with D again on my notebook at home 
and realized,

that I have a broken installation.
Even the minimal D "hello world" throws an error at execution.
Speicherzugriffsfehler (Speicherabzug geschrieben) aka. core dump

Compiling with ldc2 still works.
Any hint?




Re: How to proceed with learning to code Windows desktop applications?

2018-02-02 Thread Martin Tschierschke via Digitalmars-d-learn

On Thursday, 1 February 2018 at 09:18:30 UTC, I Lindström wrote:
[...]


And thank you all for your ideas and suggestions. I'll try some 
out and see what works.


I found this useful:
https://github.com/adamdruppe/arsd/blob/master/simpledisplay.d




Last post from me not displayed on web frontend?

2017-09-22 Thread Martin Tschierschke via Digitalmars-d-learn

This post is to try if it works now.
But I got an answer from Adam...

Thank you.


Parsing mbox file to display with vibe.d

2017-09-22 Thread Martin Tschierschke via Digitalmars-d-learn

Hello,
Parsing mbox file (/var/spool/mail/... on a Ubuntu machine)
and splitting to a range or array of mail objects.

Has anyone done this with D? please give me hint. (DUB, git, this 
forum?)


Or should I start with formail (-s) as a subprocess?

(At first step,  I want to run a vibe.d server to display all 
Cron Messages which I will forward to one special account to view 
them in a browser.


At first I thought about setting up Squirrel Mail or something 
similar for the job, but then by simply splitting the mbox and 
displaying the content in a html-table I might get what I need. )


Regards mt.


Re: Most convenient way to write a loop with fixed length and no need for the index?

2017-09-09 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 30 June 2017 at 08:19:07 UTC, Anton Fediushin wrote:
On Friday, 30 June 2017 at 07:44:45 UTC, Martin Tschierschke 
wrote:

What do I have to do, to make this work?

iota(number).each!...command_x(a...);command_y(b...);command_z(c..))



You can use it like this:
iota(10).each!((x) { command1(); command2(); ... });


I missed this syntax!



Or there is a short syntax (lambda):
iota(10).each!((x) => command1());




See http://dlang.org/spec/expression.html#Lambda for more info 
about lambdas.




Or is there something like number.times!{} possible?

You can write your own function. It is simple.
void times(alias fun)(size_t i) {
foreach(unused;0..i)
fun();
}

and use it like this:
10.times!({ writeln("yaaay"); });


Thank You! Ali and Anton!
D is so cool! :D

ps. This post was written but not send... on June 30...



Re: Should `dub run` prints its output to STDERR?

2017-09-09 Thread Martin Tschierschke via Digitalmars-d-learn

On Saturday, 9 September 2017 at 05:58:59 UTC, Ali Çehreli wrote:

On 09/08/2017 09:51 PM, Ky-Anh Huynh wrote:
> When I execute a program thanks to dub, `dub` also prints its
> information to STDOUT:

Try dub's --quiet command line switch.

Ali


Can I configure this also in dub.json (dub.sdl)?
Specially --parallel switch?



Re: Compare times: file modification time

2017-08-02 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 2 August 2017 at 13:32:46 UTC, Adam D. Ruppe wrote:
On Wednesday, 2 August 2017 at 13:25:25 UTC, Martin 
Tschierschke wrote:
I get a SysTime, how to check if it is older than an interval 
(1 day)?

D/Phobos idiomatically?


   if(Clock.currTime - timeLastModified("aa.d") > 1.days) {
  // older
   }

Thank you Adam. So simple!



Compare times: file modification time

2017-08-02 Thread Martin Tschierschke via Digitalmars-d-learn

With

import std.file:timeLastModified;
auto time = timeLastModified(source);

I get a SysTime, how to check if it is older than an interval (1 
day)?

D/Phobos idiomatically?

(Currently I am using 
(Clock.currTime().toUnixTime-time.toUnixTime)< 60*60*24)).


Regards mt.


Re: Compile Time versus Run Time

2017-07-31 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 31 July 2017 at 15:57:28 UTC, Anonymouse wrote:

On Monday, 31 July 2017 at 15:46:47 UTC, inevzxui wrote:
On Monday, 31 July 2017 at 15:43:21 UTC, Martin Tschierschke 
wrote:

[...]
But the parameters are not checked at compile-time unless you 
specifically pass the pattern string as a template parameter. I 
think its immutability implicitly converting it into a template 
parameter is what's what he's talking about.


import std.stdio;

void main(string[] args)
{
writefln!"%s"(); // compile-time assert
writefln("%s");  // runtime exception, though everything 
needed for a compile-time assert was inferable during 
compilation

}


This is exactly the "use case", I thought about: How to avoid 
runtime errors, if at compile time the problem might be detected.


Compile Time versus Run Time

2017-07-31 Thread Martin Tschierschke via Digitalmars-d-learn
As a rookie in D programming I try to understand the power of 
templated functions with compile time parameters. With DMD 2.074 
a compile time format

(auto output = format!("Print this %s")(var);)

was introduced, now we all know that very many of this format 
strings are immutable, so wouldn't it be cool to automatically 
detect this and use the compile time version?


Without the need to think about it and to use an other syntax?
Is this theoretically possible?

Regards mt.




howto touch a file - setTimes

2017-07-24 Thread Martin Tschierschke via Digitalmars-d-learn

When I tried to set the atime and mtime of a file (f) via:

import std.datetime;
auto time = Clock.currTime();
setTimes(f,time,time);

I get "Operation not permitted."

This is caused on linux by the rule, that if you are not the 
owner of the file

you may only set the mtime of a file to current time.

A simple "touch filename" in terminal works.

Any hint? Do I have to use execute("touch filename")?



Re: how to harvest the results of tasks from a taskpool?

2017-07-05 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 5 July 2017 at 13:55:22 UTC, Martin wrote:

Hi,

i have a coulpe of different machines with MySQL Servers 
running on it.
Now, i want to execute queries for all Databases at the same 
time and collect the Result to process it.


I am new to the parallelism - so maybe i understand something 
totaly wrong.

What i tring is something like this:


{
 auto tPool = new TaskPool();
 forach(server ; servers)
 {
  auto task = task!queryWorker(query);
  tPool.put(task);
 }

 tPool.finish(true);
//> how to collect the results now? <---

}

row[] queryWorker(string query) {

 //rows = result of the query

 return rows;
}


btw.. how to markup code in this forum?
I tested a much simpler approach with the following 
setup/structure?:


// a shared array of results where each result is again an array;
Rows results[];

// using parallel foreach
foreach(i,server;servers.parallel){
 result[i] = request(server).array;;
}
Now every array of rows is accessible in result[]?

Tested this construct with parallel curl requests:

time ./parallel_curl
Site www.dlang.org. Page has length:31607
Site forum.dlang.org. Page has length:24358
Site code.dlang.org. Page has length:36477
Site www.google.com. Page has length:10628

real0m0.836s
user0m0.137s
sys 0m0.034s

Without parallel:

real0m2.424s
user0m0.722s
sys 0m0.209s

This is the code:

import std.stdio;
import std.net.curl;
import std.parallelism;
void main()
{
enum string[] tospider = 
["www.dlang.org","forum.dlang.org","code.dlang.org","www.google.com"];

char[][tospider.length] results;
foreach(i,site;tospider.parallel){
 results[i] = get(site);
}

foreach(i,e;results){
writeln("Site ", tospider[i],". Page has 
length:",e.length);

}
}


Will try to use this approach to collect some elastic seach 
results and look if it speeds up on an 8 core machine.






Re: Need simple sound

2017-07-05 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 5 July 2017 at 10:19:54 UTC, Sebastiaan Koppe wrote:
On Wednesday, 5 July 2017 at 09:43:05 UTC, Martin Tschierschke 
wrote:
On Wednesday, 5 July 2017 at 07:21:45 UTC, Sebastiaan Koppe 
wrote:

On Wednesday, 5 July 2017 at 05:34:37 UTC, FoxyBrown wrote:
On Tuesday, 4 July 2017 at 20:37:44 UTC, Sebastiaan Koppe 
wrote:

Portaudio is simple as well. And nice cross platform.


are there any bindings?


Sure, see http://code.dlang.org/packages/portaudio


Sorry, for that question but now, as I have several different 
options -
all not 'overdocumented' -  so what would be the shortest 
possible D program waiting for input and playing a sound from 
a file in parallel?


Something short like the single-file dub example...?

#!/usr/bin/env dub
/+ dub.sdl:
name "hello"
+/
void main() {

 writef("Do you like the music?");
  char[] answer;
  answer = readln();
  writef("This was your Answer: ", answer);

}


This one plays a wav file. Couldn't get dub to do single-file 
on it. It kept giving linker errors. (Took example from 
https://github.com/v--/portaudio/blob/master/examples/pa_test.d)

[...]

 Lerror:
stderr.writefln("error %s", 
to!string(Pa_GetErrorText(err)));

return 1;
}

Thank you!

Without the error handling it would be quite simple :-)
So, the following process starts the music in main, it is just to 
clarify the process for me: In main:


//1
PaStream* stream;
Sound input = decodeWAV("FILE.wav");
auto audio = Audio(input);
Pa_Initialize();
Pa_OpenDefaultStream(,...input...,);
//2
Pa_StartStream(stream);
//3
Pa_StopStream(stream);
Pa_CloseStream(stream);

For my purpose I will try to encapsulate it all in 3 additional 
own methods on top of it:

//1
 auto myinput = InitWav("File.wav");
//2
 PlaySound(myinput,volume=default, length=max_length);
//3
 StopSound(myinput);

With a new Struct myinput to handle input,audio and stream.

Thank you all for your help!




Re: Need simple sound

2017-07-05 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 5 July 2017 at 07:21:45 UTC, Sebastiaan Koppe wrote:

On Wednesday, 5 July 2017 at 05:34:37 UTC, FoxyBrown wrote:
On Tuesday, 4 July 2017 at 20:37:44 UTC, Sebastiaan Koppe 
wrote:

Portaudio is simple as well. And nice cross platform.


are there any bindings?


Sure, see http://code.dlang.org/packages/portaudio


Sorry, for that question but now, as I have several different 
options -
all not 'overdocumented' -  so what would be the shortest 
possible D program waiting for input and playing a sound from a 
file in parallel?


Something short like the single-file dub example...?

#!/usr/bin/env dub
/+ dub.sdl:
name "hello"
+/
void main() {

 writef("Do you like the music?");
  char[] answer;
  answer = readln();
  writef("This was your Answer: ", answer);

}







Re: Need simple sound

2017-07-04 Thread Martin Tschierschke via Digitalmars-d-learn

On Tuesday, 4 July 2017 at 11:59:33 UTC, Vladimir Panteleev wrote:
On Monday, 3 July 2017 at 10:40:03 UTC, Martin Tschierschke 
wrote:

On Monday, 3 July 2017 at 09:24:35 UTC, Guillaume Piolat wrote:
On Monday, 3 July 2017 at 08:55:20 UTC, Martin Tschierschke 
wrote:
Hello for a simple game I would like to add some very simple 
sound, not much different than the beeps of "PAC Man". Is 
there anything I can use for this?


DerelictSDL supports the loading of SDL_mixer, which makes it 
very practical.
Thank you for the hint, a short google search was not so 
successful, can you give me

an additional  hint / link?
I think I would have to produce a time series of a sinus for 
example and to play it?


Here's a program that plays some square waves:

https://dump.thecybershadow.net/9db4fcd7b004e5dfccf537e49cbb72a6/test.d


Cool, will try!


Re: Need simple sound

2017-07-03 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 3 July 2017 at 09:24:35 UTC, Guillaume Piolat wrote:
On Monday, 3 July 2017 at 08:55:20 UTC, Martin Tschierschke 
wrote:
Hello for a simple game I would like to add some very simple 
sound, not much different than the beeps of "PAC Man". Is 
there anything I can use for this?


DerelictSDL supports the loading of SDL_mixer, which makes it 
very practical.
Thank you for the hint, a short google search was not so 
successful, can you give me

an additional  hint / link?
I think I would have to produce a time series of a sinus for 
example and to play it?







Need simple sound

2017-07-03 Thread Martin Tschierschke via Digitalmars-d-learn
Hello for a simple game I would like to add some very simple 
sound, not much different than the beeps of "PAC Man". Is there 
anything I can use for this?


Re: mysql-native + vibe.d example

2017-06-30 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 30 June 2017 at 00:52:28 UTC, crimaniak wrote:

Hi!
Moving my project from mysql-lited to mysql-native I faced the 
problem with null pointer error inside of mysql-native:



[...]
It seems I am doing something wrong so myself-native fails to 
detect it in isValid(). So I search for example how to use 
mysql-native in real multi-threaded vibe.d application with 
usage of MySQLPool. Please do not point me to basic example 
provided with package because it is single thread.

Thanks.
Sorry, can not help, but would be very interested to learn how to 
do a


 real multi-threaded vibe.d with mysql

So if you find a solution, please make an simplified example for 
vibe.d documentation!

Sönke might include it into vibe.d docs.


Most convenient way to write a loop with fixed length and no need for the index?

2017-06-30 Thread Martin Tschierschke via Digitalmars-d-learn

What do I have to do, to make this work?

iota(number).each!...command_x(a...);command_y(b...);command_z(c..))
 ^?
how to write the lambda?

Similar to the ruby (1..number).each{ commands...}

Don't want to write the following, because the index i is not 
used inside the loop

and this should be clear when reading it:

  for (i=0;i

Re: How to add class in DIET template

2017-06-23 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 23 June 2017 at 06:59:22 UTC, Suliman wrote:

I need to get external variable and make class by it's value

- string mystr = "lng-" ~ language;
- foreach(i, line; arrayOfLines )
li
code.mystr #{line}

I need to get HTML code like this:


some D code


But class name become "mystr" and I am getting:


some D code


How to fix it?
You can use the html syntax for the class parameter, the 
funny/nice thing is, that mystr can be used directly without 
"#{}" around.


code(class=mystr) #{line}

works.


Re: Operator Overloading + / ~

2017-06-19 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 19 June 2017 at 12:22:43 UTC, ketmar wrote:

Martin Tschierschke wrote:

Just a thought it might be useful for cut-n-paste when porting 
code:


Would it be possible to define an operator overloading for 
'+'-Operator for strings to work as append? (like ~).
I understand, that '~' is in general a better choice than '+', 
so this is of more theoretical interest.
It is clear to me, that when I define my own string type this 
is possible.


Regards mt.


nope. it is not possible to overload operators for built-in 
types (and string is just an aliased array).

Thank you for lightning fast response :-)



Operator Overloading + / ~

2017-06-19 Thread Martin Tschierschke via Digitalmars-d-learn
Just a thought it might be useful for cut-n-paste when porting 
code:


Would it be possible to define an operator overloading for 
'+'-Operator for strings to work as append? (like ~).
I understand, that '~' is in general a better choice than '+', so 
this is of more theoretical interest.
It is clear to me, that when I define my own string type this is 
possible.


Regards mt.



Re: Playing arround with mixin - alias?

2017-04-21 Thread Martin Tschierschke via Digitalmars-d-learn
On Friday, 21 April 2017 at 11:58:13 UTC, Martin Tschierschke 
wrote:

On Friday, 21 April 2017 at 10:31:46 UTC, ketmar wrote:

biozic wrote:


I thought way to complicated:
Just define the string at top:

enum exho="auto mixinter(string x)(){return mixin(interp!x);}
auto exho(string x)(){return 
mixin(\"writeln(\"~interp!x~\")\");}";


Then use:

mixin(exho);
exho!"${name} you are app. ${age*365} days old";

In your scope!






Re: Playing arround with mixin - alias?

2017-04-21 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 21 April 2017 at 10:31:46 UTC, ketmar wrote:

biozic wrote:


On Friday, 21 April 2017 at 09:42:33 UTC, ketmar wrote:

Martin Tschierschke wrote:


Is it possible to define an alias for something like

mixin(import("local_function_file.d"));

to write only

use_local_function;

which will be translated to: 
mixin(import("local_function_file.d"));


(this additionally needs the file local_function_file.d in 
source/ +
-J./source as parameter for dmd aka.  dflags "-J./source" in 
dub.sdl)


Regards mt.


nope. the best you can get is `mixin use_local_function;`.


Would there be an advantage compared to a simple `import 
local_function_file;`?


i doubt so.

So my "solution" on how to get a short cut for using:

writeln(mixin(interp!"${name} you are app. ${age*365} days old"));


// first place in source/exho.d the following code:

auto mixinter(string x)(){return mixin(interp!x);}
auto exho(string x)(){return mixin("writeln("~interp!x~")");}

later compile this with -J./source

source/app.d:

import scriptlike;

auto insert(string name)(){return import(name);}
alias insert!"exho.d" use_exho;



void main()
{
  auto name = userInput!string("Please enter your name");
  auto age = userInput!int("And your age");

//Now you can write in  every scope you need it:
  mixin(use_exho);
  exho!"${name} you are app. ${age*365} days old";

// Which looks little nicer than:
// writeln(mixin(interp!"${name} you are app. ${age*365} days 
old"));


// or if you need the result in a var:

  mixin(use_exho);
  auto var = mixinter!"${name} you are app. ${age*365} days old";

  writeln(var);
}

you may even name the alias just exho and write:

 alias insert!"exho.d" exho;

 mixin(exho);
 exho!"${name} you are app. ${age*365} days old";

(exho was derived from shell echo with mi_x_in)



Playing arround with mixin - alias?

2017-04-21 Thread Martin Tschierschke via Digitalmars-d-learn

Is it possible to define an alias for something like

mixin(import("local_function_file.d"));

to write only

   use_local_function;

which will be translated to: 
mixin(import("local_function_file.d"));


(this additionally needs the file local_function_file.d in 
source/ +
-J./source as parameter for dmd aka.  dflags "-J./source" in 
dub.sdl)


Regards mt.


Re: ndslice summary please

2017-04-13 Thread Martin Tschierschke via Digitalmars-d-learn

On Thursday, 13 April 2017 at 08:47:16 UTC, Ali Çehreli wrote:
I haven't played with ndslice nor followed its deprecation 
discussions. Could someone summarize it for us please. Also, is 
it still used outside Phobos or is Ilya or someone else 
rewriting it?


Ali


We should additionally mention sometimes, that the naming of 
ndslice is derived from ndarray
and this is from N-dimensional Array. No one searching for N - 
dimensional Array OR Matrix will find ndslice, without this info 
easily. Just try a google search: "dlang n dimesional array"

Regards mt.


CTFE using of replaceAll from std.regex posible?

2017-04-12 Thread Martin Tschierschke via Digitalmars-d-learn

Hello,
when trying to process an string at compile time with
 ...
 auto reg = ctRegex!`as\ [a-z]+`;
 enum replaced = replaceAll(call,reg,"");

I get:
/usr/include/dmd/phobos/std/regex/package.d(708,34): Error: 
malloc cannot be interpreted at compile time, because it has no 
available source code
/usr/include/dmd/phobos/std/regex/package.d(708,27):
called from here: enforce(malloc(size), delegate const(char)[]() 
=> "malloc failed", 
"/usr/include/dmd/phobos/std/regex/package.d", 708LU)
/usr/include/dmd/phobos/std/regex/package.d(832,34):
called from here: ((RegexMatch!(string, BacktrackingMatcher) 
__slRegex3165 = RegexMatch(BacktrackingMatcher(Regex(null, null, 
null, 0u, 0u, 0u, 0u, 0u, null, null, null, ShiftOr(null, 0u, 
0u)), null, Input(null, 0LU), 0LU, '\U', false, 0u, 0u, 
0LU, null, null, null, null), null, Captures(null, 0, null, , 0u, 
0u, 0u, null), null);) , __slRegex3165).this(input, re)
/usr/include/dmd/phobos/std/regex/package.d(1049,48):
called from here: matchMany(input, re)
/usr/include/dmd/phobos/std/regex/package.d(906,26):
called from here: matchAll(input, re)
/usr/include/dmd/phobos/std/regex/package.d(1345,69):
called from here: replaceAllWith(input, re)
src/app.d(13,29):called from here: replaceAll(call, reg, 
"")


It there a way to use "replaceAll" at compile time?

Regards mt.


Re: Getting nice print of struct for debugging

2017-02-27 Thread Martin Tschierschke via Digitalmars-d-learn

On Saturday, 25 February 2017 at 01:30:09 UTC, Minty Fresh wrote:
On Saturday, 25 February 2017 at 01:27:09 UTC, Minty Fresh 
wrote:
On Wednesday, 22 February 2017 at 11:18:15 UTC, Martin 
Tschierschke wrote:

[...]


Since structs are Plain-old Data and don't do inheritance, the 
best option is a template mixin.


ie.

  template mixin PrettyPrint
  {
  string toString()
  {
  // . . .
  }
  }

From there, you can mix it into any struct you want.

  struct MyStruct
  {
  mixin PrettyPrint;
  }

If you're familiar with Rails, this is similar to a Concern.


Errata on that. Should actually be declared as:

  mixin template PrettyPrint()

This is why I shouldn't make posts from my phone.


Thank you, but this solution from Kevin Brogan, is an good 
alternative,
to add a special dump function globally, so no need to modify the 
struct definitions.


https://forum.dlang.org/post/yewavntuyutdvejwj...@forum.dlang.org

His solution:

import std.traits;

void main()
{
WSADATA wsa;
dump!wsa;
}

void dump(alias variable)()
{
writeln("\nDumping ",typeid(typeof(variable)),":\n");
writeln(variable.stringof, " = \n{");
foreach(member; FieldNameTuple!(typeof(variable)))
{
writeln("\t", member, ": ", mixin("variable."~member) );
}
writeln("}\n");
}





Re: Getting nice print of struct for debugging

2017-02-22 Thread Martin Tschierschke via Digitalmars-d-learn
On Tuesday, 21 February 2017 at 14:02:54 UTC, Jacob Carlborg 
wrote:

[...]

Yes, this works, I would say this is the simplest:

MyStruct s;

foreach (index, name ; FieldNameTuple!MyStruct)
writefln("%s: %s", name, s.tupleof[index]);

If you want something more close to "send" in Ruby, you need to 
use a string mixin, like this:


foreach (name ; FieldNameTuple!MyStruct)
writefln("%s: %s", name, mixin("s." ~ name));

The string mixin example works for methods, opDispatch and 
similar as well. The tupleof example, the first one, works only 
for fields.

Exactly what I was looking for, **thank you!**
Both ways of accessing the struct elements are very interesting,
giving an impression what is possible with D.


Is it possible to overwrite "toString" for all structs in one 
step?


Regards mt.




Re: Getting nice print of struct for debugging

2017-02-20 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 20 February 2017 at 16:18:58 UTC, Paul Backus wrote:
On Monday, 20 February 2017 at 16:04:17 UTC, Martin 
Tschierschke wrote:

Hello,
I have a little program where I am filling a struct with 
values from an regex match.
Now I want to display the content of the struct for debugging 
purpose.


I believe the easiest way to do this is to define a custom 
toString member function for your struct. For example:


struct MyStruct {
int x;
double y;
string s;

string toString() {
import std.format: format;

return "MyStruct(x: %d, y: %f, s: \"%s\")".format(x, y, 
s);

}
}

void main() {
import std.stdio: writeln;

MyStruct foo;
foo.x =2; foo.y = 3.14; foo.s = "the quick brown fox";

writeln(foo); // Prints MyStruct(x: 2, y: 3.14, s: "the 
quick brown fox")

}
Good suggestion, thank you! Then the definition is near the 
struct definition and I do not need to care about what to call, 
just writeln(myvar); cool!





Getting nice print of struct for debugging

2017-02-20 Thread Martin Tschierschke via Digitalmars-d-learn

Hello,
I have a little program where I am filling a struct with values 
from an regex match.
Now I want to display the content of the struct for debugging 
purpose.


If struct is named MyStruct

I can print a list of the field names with:

foreach(fieldname;FieldNameTuple!MyStruct){writef("%s 
",fieldname);}


If myvar is of type MyStruct how can I make a table like:

fieldname_1: value_1
fieldname_2: value_2
.
.
fieldname_n: value_n

Is there a way to do this with a single expression in D.

Similar to a ruby call myvar.send(fieldname) to get the value 
from fieldname inside a loop?
write(myvar); sure is working directly but I want to get the 
field names displayed, too.


(A work around might be work with the format("%s",myvar) string 
and extract the values with an index?)


Regards mt.



Re: Vibe.d help

2016-09-26 Thread Martin Tschierschke via Digitalmars-d-learn
On Friday, 23 September 2016 at 21:32:59 UTC, Gestalt Theory 
wrote:
On Thursday, 22 September 2016 at 09:14:46 UTC, Martin 
Tschierschke wrote:
On Thursday, 22 September 2016 at 01:38:12 UTC, Gestalt Theory 
wrote:



3. How to serve static files properly?



sendFile(req, res, Path(req.path));

Does the trick inside the handler.


@5. There is a solution, hopefully I can find the link and 
post it later.


Any news on this?

Sorry, I have problems to find the right link:

It is mentioned here: http://vibed.org/features

-> Integrated load balancing (bottom of page)

And here you find the part for template caching, an option with 
in the new template engine:

->Experimental HTML template caching
https://github.com/rejectedsoftware/diet-ng

But the best place to ask would be in the vibe.d forum, where 
Sönke is able and willing to help!

http://vibed.org/ -> http://forum.rejectedsoftware.com/

Regards mt.






Re: Vibe.d help

2016-09-22 Thread Martin Tschierschke via Digitalmars-d-learn
On Thursday, 22 September 2016 at 01:38:12 UTC, Gestalt Theory 
wrote:
1. I get this error when trying to run a project in VS. dub 
doesn't give the error.


First-chance exception: core.exception.AssertError free() 
called with null array. at 
vibe-d-0.7.26\source\vibe\utils\memory.d(110)


It constantly pops up then I get an access violation and crash.


2. Many vibe.d HTTP Server options seem not to be implemented. 
Is this still the case? e.g., 
http://vibed.org/api/vibe.http.server/HTTPServerSettings.maxRequestTime


3. How to serve static files properly?

void images(HTTPServerRequest req, HTTPServerResponse res)
{
writeln("images Request");
write("Path = "); writeln(req.fullURL);
// Somehow reship request out
}

...

router.get("/images/*", );


I would like to be able to serve them but also log or redirect 
if possible. The messages are written. I tried to also serve 
directly and it didn't work, which is why I used a handler in 
the first place.


router.get("/images/*", serveStaticFiles("images/"));

I imagine the path is not correct. I am on windows and created 
an images sub dir in the projects(same depth as views, etc) but 
the images were not served. I didn't want to hard code this 
path, maybe it should be?

[...]
5. Many other frameworks seem to support "hot swapping" of 
files while the sever is running rather than having to 
recompile. Recompiling the diet templates/project is slow and 
requires restarting the server and all that. Is there any way 
to get vibe.d to automatically monitor the projects folder or 
templates for changes and then somehow recompile and update/etc?


Thanks.


Just to point 3. I hope I can give a hint, the problem is, that
the match is not the * but /images/*, so
router.get("/images/*", serveStaticFiles("images/"))

will look in PROJECTHOME/images/images/ for the file.

For my .css files located in

PROJECTHOME/public/styles/

I used:
router.get("/styles/*", serveStaticFiles("public/"))

if you put your images in
PROJECTHOME/public/images

router.get("/images/*", serveStaticFiles("public/"));
should work.

@5. There is a solution, hopefully I can find the link and post 
it later.




Re: Can vibe d leverage existing web technologies?

2016-09-16 Thread Martin Tschierschke via Digitalmars-d-learn
On Thursday, 15 September 2016 at 20:56:19 UTC, Intersteller 
wrote:
On Thursday, 15 September 2016 at 14:31:28 UTC, Martin 
Tschierschke wrote:
On Tuesday, 13 September 2016 at 23:45:18 UTC, Intersteller 
wrote:
vibe.d does not have much lateral support as the most commons 
web technologies do.  Can vibe.d leverage pre-existing techs 
such as php, ruby/rails, etc? Starting from scratch and 
having to build a robust and secure framework is really not 
the way to go.


A good way to mix different technologies is to use a Apache or 
nginx proxy on the same server, so you can start using vibe.d 
for some parts and keep the rest at its place.


Regards mt.


How is this done? How can it be done smoothly? I'm not sure how 
to partition the work load. While, say, some pages might be 
served from php, and others from vibe2, etc, it seems like it 
would be nightmare to maintain consistency and interactivity.


First you need to run vibe.d and the .php part on the same data
(mysql for example).
Lets say you have a special feature -  like latest news, than you 
build the rendering of this with vibe.d and the rendering of the 
single news are still in php.
Than you may move this to vibe.d later and keep only your back 
end, for editing
the content in php. So the most read pages are served by vibe 
first.


The "only" problem is you have to build your layout twice,
in php and as diet template. :-(

An other option might be, to start with the admin back end, where 
layout is not so critical and add additional features like 
statistics or a special dashboard?


Regards mt.





Re: vibe.d PaaS

2016-09-16 Thread Martin Tschierschke via Digitalmars-d-learn
On Wednesday, 14 September 2016 at 09:01:11 UTC, Guillaume Piolat 
wrote:

Is there vibe.d hosting sold anywhere?


I am using this one: https://www.menkisys.de/

in the moment vibe.d only for tests.
But with an Rails web service, using a small parser for email 
with attached pdf,
 written in D, it is only 5 Euro/month for a virtual machine 
running ubuntu.


Oh, it seams they only offer support in German language(?)...

Regards mt.



Re: Can vibe d leverage existing web technologies?

2016-09-15 Thread Martin Tschierschke via Digitalmars-d-learn

On Tuesday, 13 September 2016 at 23:45:18 UTC, Intersteller wrote:
vibe.d does not have much lateral support as the most commons 
web technologies do.  Can vibe.d leverage pre-existing techs 
such as php, ruby/rails, etc? Starting from scratch and having 
to build a robust and secure framework is really not the way to 
go.


A good way to mix different technologies is to use a Apache or 
nginx proxy on the same server, so you can start using vibe.d for 
some parts and keep the rest at its place.


Regards mt.


Re: C binding with D function

2016-08-04 Thread Martin Tschierschke via Digitalmars-d-learn

On Thursday, 4 August 2016 at 12:14:48 UTC, Adam D. Ruppe wrote:

On Thursday, 4 August 2016 at 10:36:05 UTC, llaine wrote:

Any idea how can I call them ?


Just like any other function. Consider this:


[...]

Compile

[...]

hi from D, Ruby user!


Thank you a lot!!! I want to use some vibe.d rendering inside 
Ruby on Rails, this

gives me a god starting point, for my experiments.

Regards mt.



Re: full path to source file __FILE__

2016-07-23 Thread Martin Tschierschke via Digitalmars-d-learn

On Thursday, 21 July 2016 at 19:54:34 UTC, Jonathan Marler wrote:
Is there a way to get the full path of the current source file? 
Something like:


__FILE_FULL_PATH__

I'm asking because I'm rewriting a batch script in D, meant to 
be ran with rdmd.  However, the script needs to know it's own 
path.  The original batch script uses the %~dp0 variable for 
this, but I'm at a loss on how to do this in D.  Since rdmd 
compiles the executable to the %TEMP% directory, thisExePath 
won't work.


BATCH
-
echo "Directory of this script is " %~dp0


What about using a wrapper around rdmd, so the program is 
executed with an
additional parameter or an environment variable containing 
"FULL_PATH".


When I started with D, I "accidentaly" wrote my own replacement 
script for rdmd
compiling xyz.d with dmd to xyz or calling xyz depending on the 
modification times of the files.


Regards mt.




Re: Best way to convert Apachelog Datetime 01/Jan/2016:02:25:10 -> 2016-01-01 02:25:10 MySQL-Datetime Format

2016-06-08 Thread Martin Tschierschke via Digitalmars-d-learn
On Wednesday, 8 June 2016 at 10:42:19 UTC, Martin Tschierschke 
wrote:

I know there are easy ways to handle this,
anyone with a code snippet for me?

I found this solution, letting the MySQL engine do the work:

  SELECT STR_TO_DATE('26/Apr/2011:13:21:58', '%d/%b/%Y:%H:%i:%S');

https://www.experts-exchange.com/questions/26992776/convert-apache-log-date-time-to-mysql.html

Maybe  there is an other short solution using the std.datetime 
and or

https://code.dlang.org/packages/dateparser ?


Best way to convert Apachelog Datetime 01/Jan/2016:02:25:10 -> 2016-01-01 02:25:10 MySQL-Datetime Format

2016-06-08 Thread Martin Tschierschke via Digitalmars-d-learn

I know there are easy ways to handle this,
anyone with a code snippet for me?

I would use two regex first to make 01,02,03... from Jan,Feb,.. 
and

second to split the result.

best regards mt.


Re: parsing HTML for a web robot (crawler) like application

2016-03-23 Thread Martin Tschierschke via Digitalmars-d-learn
On Wednesday, 23 March 2016 at 09:06:37 UTC, Rene Zwanenburg 
wrote:

[...]


Adam's dom.d will get you pretty far. I believe it can also 
handle documents that aren't completely well-formed.


https://github.com/adamdruppe/arsd/blob/master/dom.d

Thank you! This forum has an incredible fast auto responder ;-)



parsing HTML for a web robot (crawler) like application

2016-03-23 Thread Martin Tschierschke via Digitalmars-d-learn

Hello!
I want to set up a web robot to detect changes on certain web 
pages or sites.
Any hint to similar projects or libraries at dub or git to look 
at,

before starting to develop my own RegExp for parsing?

Best regards
mt.


Re: Memory Efficient HashSet

2016-03-10 Thread Martin Tschierschke via Digitalmars-d-learn

On Wednesday, 9 March 2016 at 22:31:50 UTC, Nordlöw wrote:
[...]

foreach (const i; iota(0, n))
{
x[i] = true; // indicate that it's stored
}

import std.stdio : writeln, readln;
writeln("Press return: ");
readln;
}

consumes 842.m MiB on my Ubuntu.

The consumption with Google's sparsehash unordered_set is about 
50 MiB.

May be the discussion associated with this post, can give help???
https://forum.dlang.org/post/mailman.217.1457590242.26339.digitalmars-d-b...@puremagic.com


I tried your little program and played around. I tried x.rehash, 
but this resulted in even more memory consumption. 80 bytes for 4 
bytes key and one bit storage seams a lot.

With smaller n it comes down to app. 60 Bytes.

With how many data sets at the end, you will have to deal?


Re: Speed up `dub`.

2016-03-07 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 7 March 2016 at 09:18:37 UTC, ciechowoj wrote:
I'm using `dub` to build project. And every time I run `dub` it 
seems to check if dependencies are up to date, which takes some 
time. Is there a way to switch of that checking? Or any other 
way to speed up building process? It really slows down my 
modify-compile-check iteration time.


A few hours ago dub.pm alias code.dlang.org was down or slow, so 
I used:


$> dub --skip-registry=all build

might be thats the reason?


Error in DUB Package Page - how to notify the Editor?

2016-01-22 Thread Martin Tschierschke via Digitalmars-d-learn
What about the idea to allow discussion entries/threads to be 
linked to dub package entries?


So they appear in DUB  and in a additional section of this forum?

So vibe.d for example comes with his own forum that is good, but 
a solution for all

would be nicer?

So coming back to my first question: How to notify the author 
about errors, with out the need for searching for him elsewhere ?


Regards mt.



Size of Compiled Program

2016-01-04 Thread Martin Tschierschke via Digitalmars-d-learn

When I was writing a small speed test - D versus Ruby,
calculating the first n prime numbers, I realized, that for small 
n

Ruby may be faster, than compiling and executing with D.
But for n = 1,000,000 D outperforms Ruby by app. 10x.

Looking at the size of my prime executable, it was around 800 kB 
with DMD

and even with optimization and "gdc -Os" > 1 MB.
Why is such a short program resulting in a so big binary?
-
import std.stdio;
import std.conv;
int[] prime; // Dynamic Array of Prime

// Ist n durch eine der zahlen in prime teilbar?
bool teilbar(int n){
for(auto i=0; prime[i]*prime[i]<=n ; i++){
if (n%prime[i]==0) return true;
}
return false;

}

void main(string[] args)   // first parameter number of primes to 
calculate

{
auto anzahl = 10; // default
prime ~= 2;   // first element of the array
if(args.length==2){
anzahl = to!int(args[1]);}
auto pruefe=1;
while (prime.length <= anzahl){
pruefe+=2;
if(!teilbar(pruefe)){
write(" ",pruefe);
prime ~= pruefe; // append the array
}
}

write("\n das wars...:",prime.length);
}





Re: Size of Compiled Program

2016-01-04 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 4 January 2016 at 14:51:59 UTC, Adam D. Ruppe wrote:
On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:

When I was writing a small speed test - D versus Ruby


The smallest possible ruby program has about ~5 MB of 
dependencies, outside the operating system (the ruby runtime 
itself).


The D program has none. It carries its runtime with it, which 
makes the executable a bit larger to compensate but helps 
compatibility with other computers because the user doesn't 
have to hunt down obscure D runtime packages.


Oh, thats interesting. When I tried to run the compiled "prime" 
on my notebook,
with the "same" Ubuntu release, I got an error, may be its 32 not 
64 Bit?

Any hint?





Re: Size of Compiled Program

2016-01-04 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 4 January 2016 at 14:01:18 UTC, Basile B. wrote:
On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:

[...]

- if debug info are generated this increases the size.
- if bounds checking is turned off there is some code generated 
for each array operation
- if contracts are not off there is a lot of assertion that 
will be generated


see also some clues here:
http://forum.dlang.org/post/mailman.20.1441974998.22025.digitalmars-d-le...@puremagic.com


Ah, thank you for that Link!


Re: Size of Compiled Program

2016-01-04 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 4 January 2016 at 14:16:54 UTC, Marc Schütz wrote:
On Monday, 4 January 2016 at 13:49:03 UTC, Martin Tschierschke 
wrote:

When I was writing a small speed test - D versus Ruby,
calculating the first n prime numbers, I realized, that for 
small n

Ruby may be faster, than compiling and executing with D.
But for n = 1,000,000 D outperforms Ruby by app. 10x.

Looking at the size of my prime executable, it was around 800 
kB with DMD

and even with optimization and "gdc -Os" > 1 MB.
Why is such a short program resulting in a so big binary?


That's probably basic these compilers statically link the 
runtime (and standard?) libraries by default. Compiling your 
program with `ldc2 -O3`, I get a binary of 28K, and stripping 
gets it down to 17K.


Ok, I will try ldc2, too.


Re: Deit variable referencing

2016-01-03 Thread Martin Tschierschke via Digitalmars-d-learn

On Saturday, 2 January 2016 at 00:15:32 UTC, Jason Jeffory wrote:

Ok, So Deit allows D code inside html... looks great.

But how do external variables work? If I create a variable in 
the server(such as a class), can an html file access it easily? 
(not having to jump through hoops)



doctype html
html
head
title D string interpolations test
body
- import std.algorithm : min;
p Four items ahead:
- foreach( i; 0 .. 4 )
- auto num = i+1;
p Item #{ num + extvar }
//- Unescaped output
p Prints 8: !{ min(10, 2*6, 8) }


here, extvar is a int located somewhere else(other deit html 
file that has ran(hopefully) or vibe.d project that created it.


(Obviously there has to be a way to get extvar)

E.g., If deit can have a special variable called context that 
each html file can access and along with the vibe.d project, 
then we can easily pass the variable.



doctype html
html
head
title D string interpolations test
body
- import std.algorithm : min;
p Four items ahead:
- foreach( i; 0 .. 4 )
- auto num = i+1;
p Item #{ num + (int)context["extvar"] }
//- Unescaped output
p Prints 8: !{ min(10, 2*6, 8) }

or whatever


I am a very new at this, but I think "the solution" is to call  
res.render! with all alias names you need.

Defining int extvar =... before; you use:

  res.render!("your-template.dt",extvar,..)

hope this helps. Regards mt.


Re: Deit Editor

2016-01-03 Thread Martin Tschierschke via Digitalmars-d-learn

On Friday, 1 January 2016 at 00:14:08 UTC, Jason Jeffory wrote:
Vibe.d uses deit files for html generation. Seems nice but 
haven't dived into it(just removes a but of nonsense and allows 
code integration for dynamic generation... sounds great!!).


But what about visual editing? It's nice to be ale to see the 
layout of the page directly without all the hassle of toggling 
back and forth between a browser and code editor. Also, there 
is the issue of syntax highlighting, code validation, etc...


I came across this

http://stackoverflow.com/questions/16080350/using-jade-with-wysiwyg-markdown-to-allow-users-to-edit-content

Any ideas to make life easier? (isn't that what it's all about?)


There was an answer pointing to 
https://www.npmjs.org/package/html2jade
and this to http://html2jade.aaron-powell.com/, which  allows you 
to convert online HTML to JADE.
So you can make your HTML layout on an traditional way and get 
the jade code.


Re: Question about mysql-d Object

2015-12-08 Thread Martin Tschierschke via Digitalmars-d-learn

On Monday, 7 December 2015 at 16:11:19 UTC, Daniel Kozak wrote:
On Monday, 7 December 2015 at 14:40:12 UTC, Martin Tschierschke 
wrote:

When I do the following:

auto mysql = new Mysql("localhost", 3306, "mt", "", 
"verwaltung");

auto rows = mysql.query("select field from my_table limit 50");

foreach(row;rows){
 writeln(row["field"]);}

// second time same loop

foreach(row;rows){
 writeln(row["field"]);}


[...]

A nested loop, did not worked either:

foreach(row;rows){
 foreach(field;row){
 writeln(field);}
}

Which other ways to access the elements of rows do I have?


[...]

what if you make array from it:
import std.array: array;
auto rows = mysql.query("select field from my_table limit 
50").array;

Thank you both for your answers!
This worked, for the first part of my question.
Now I took a work around, getting the field names in a separate 
mysql-request,

but they should be available in the row object, too?



Re: Question about mysql-d Object

2015-12-08 Thread Martin Tschierschke via Digitalmars-d-learn

On Tuesday, 8 December 2015 at 15:14:06 UTC, Daniel Kozak wrote:
[...]

>> A nested loop, did not worked either:
>>
>> foreach(row;rows){
>>  foreach(field;row){
>>  writeln(field);}
>> }

[...]

Now I took a work around, getting the field names in a separate
mysql-request,
but they should be available in the row object, too?



rows.fieldNames() this one is better result type is string[]

Thank you!!!



Question about mysql-d Object

2015-12-07 Thread Martin Tschierschke via Digitalmars-d-learn

When I do the following:

auto mysql = new Mysql("localhost", 3306, "mt", "", "verwaltung");
auto rows = mysql.query("select field from my_table limit 50");

foreach(row;rows){
 writeln(row["field"]);}

// second time same loop

foreach(row;rows){
 writeln(row["field"]);}

I only get the output of the first loop (50 lines), probably this 
is a feature

not a bug, but what kind of Object is rows?

A nested loop, did not worked either:

foreach(row;rows){
 foreach(field;row){
 writeln(field);}
}

Which other ways to access the elements of rows do I have?

Sorry, but I am very new on D, (it may be the best language 
available, I don't know yet, but it is really the most 
interesting!) thank you!