Accessing a txt file resource

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daveplummermd
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Accessing a txt file resource

Unread post by daveplummermd » 2 Oct 2018 14:29

Guys
I have added a text file as a resource in a package.
How do I access the text contents of that file?
Image

Thanks in advance

dave
Dave Plummer

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Thomas Linder Puls
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Re: Accessing a txt file resource

Unread post by Thomas Linder Puls » 2 Oct 2018 20:19

Adding a text file (and many other kinds of files) does not have any influence on the resulting program (the files will not be embedded in the program in any form).

The only difference it makes is that the file is present in the project tree, and if you double click it there it will open in an editor.

This can be handy for many reasons, you could ofor example have a to-do list, or if you have some files that will be used at run time you can manage them in the IDE, …


By the way, the image you have added looks strange (I think it is because it is not publicly accessible).
Regards Thomas Linder Puls
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Martin Meyer
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Re: Accessing a txt file resource

Unread post by Martin Meyer » 3 Oct 2018 14:33

Maybe the #bininclude compiler directive could help you. By it your text file can be included as a binary. The binary can be converted then to a string.

To demonstrate it take for example main.pro as the text file. It is coded in UTF-8 with a leading byte order mark of 3 bytes. Create a new console application project and replace the code in main.pro by

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implement main   constants     text8 : string8 = uncheckedConvert(string8, #bininclude(@"main.pro")).   clauses     run() :-         Str8 = string8::fromPosition(text8, 3), %remove BOM         Str = string8::fromUtf8(Str8), %convert to UTF-16         stdIO::write(Str).   end implement main   goal     console::runUtf8(main::run).
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Thomas Linder Puls
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Re: Accessing a txt file resource

Unread post by Thomas Linder Puls » 3 Oct 2018 20:09

Actually, the next Visual Prolog version will have a #stringinclude directive similar to #bininclude but resulting in a string.

Using #bininclude you cannot be sure that text8 is null-terminated. Therefore this code is safer:

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implement main   constants     text8_bin : binary = #bininclude(@"main.pro").   clauses     run() :-         Len = binary::getSize(text8_bin),         Text8 = uncheckedConvert(string8, text8_bin),         Str8 = string8::fromPosition(Text8, 3), %remove BOM         Str = string8::fromUtf8(Str8, Len - 3), % convert to UTF-16         stdio::write(Str).   end implement main
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Martin Meyer
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Re: Accessing a txt file resource

Unread post by Martin Meyer » 3 Oct 2018 20:17

I supposed the constant in my example is null terminated, because the Language Reference says
When creating a binary constant the compiler adds the EOS symbol immediately after this constant, which makes safe the directive usages like this:

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constants     text : string = uncheckedConvert(string, #bininclude("text.txt")).     % Here text.txt is a text file, which is normally not text zero terminated
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Thomas Linder Puls
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Re: Accessing a txt file resource

Unread post by Thomas Linder Puls » 3 Oct 2018 22:49

OK, I had forgotten that we add such a null-character, so your version is fine.

Actually, we discussed this quite recently in the team and considered adding a null-char after a #bininclude, so we must all have forgotten that such one is already added :D. Anyways, we decided that #stringinclude would be a better feature :wink:.
Regards Thomas Linder Puls
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daveplummermd
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Re: Accessing a txt file resource

Unread post by daveplummermd » 6 Oct 2018 21:30

looking forward to it. Good addition.
Dave Plummer

Harrison Pratt
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Re: Accessing a txt file resource

Unread post by Harrison Pratt » 7 Oct 2018 3:17

I use an interface (.i) file tor embed large strings in an application. The string constant syntax7z is globally visible throughout the application. A rudimentary example is below.

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interface aTest     open core constants     syntax7z : string = "Usage: 7z <command> [<switches>...] <archive_name> [<file_names>...]   <Commands>   a : Add files to archive   b : Benchmark   d : Delete files from archive ... etc. ". end interface aTest

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%-- somewhere in the application stdio::write("\n", syntax7z ), ... etc.

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