[dsvr]

Thanks for your feedback. You can see the equivalent C code for any statement pretty easy. For example, if you go to "tutorials", then "tutorial-stock_app", and follow the tutorial instructions, you can always see the generated C code, which would be in:

  /var/lib/vv/bld/stockapp/__stock.o.c

(so here "stock" is the application name and there's "stock.v" file).

For example, when you see this Vely statement in stock.v (which obviously obtains input parameters from either GET or POST request):

  input-param stock_name

this is line 9 in stock.v.

All you need to do is look for:

  #line 9 "stock.v"

in the generated code (which is /var/lib/vv/bld/stock/__stock.o.c), in this case it's:

  char *stock_name = vey_get_input_param (vey_get_config()->ctx.req, "stock_name")

So in this case, it's just one line of C code. In other cases, it may be many lines. For example, Vely statement which apparently runs the INSERT SQL query:

  run-query#add_data@db = "insert into stock (stock_name, stock_price) vaues ('%s', '%s') on duplicate key update stock_price='%s'" : stock_name, stock_price, stock_price

This is on line 12 in stock.v, and you can simply search for

  #line 12 "stock.v"

in /var/lib/vv/bld/stock/__stock.o.c file. In this case, the generated code looks like:

  VV_UNUSED (_column_count_add_data);
  vely_get_config()->ctx.db->ind_current_db=0;
  static void *_sql_prep_add_data_stock_v_649 = NULL;
  _is_input_used_add_data[0]=1;
  _is_input_used_add_data[1]=1;
  _is_input_used_add_data[2]=1;
  add_data = "insert into stock (stock_name, stock_price) values ('%s', '%s') on duplicate key update stock_price='%s'";
  const char *fname_loc_add_data = "stock.v";
  num lnum_add_data = 12;
  vely_location (&fname_loc_add_data, &lnum_add_data, 1);
  vely_make_SQL (&_sql_buf_add_data, 3, add_data , _is_input_used_add_data[0]==1 ?  (stock_name) : NULL , _is_input_used_add_data[1]==1 ?  (stock_price) : NULL , _is_input_used_add_data[2]==1 ?  (stock_price) : NULL );
  if (_qry_executed_add_data == 1) {vely_report_error("Query [add_data] has executed the second time; if you want to execute the same query twice in a row without a loop-query, use different queries with the same query text (or variable) if that is your intention, file [stock.v], line number [12] ");}
  _qry_executed_add_data = 1;
  vely_execute_SQL (_sql_buf_add_data, &_arow_add_data, (const char**)&_err_add_data, (const char**)&_errm_add_data, 0, 1, 0, &_sql_prep_add_data_stock_v_649, _sql_paramcount_add_data, _sql_params_add_data);
  _nrow_add_data=0;
  vely_db_free_result ();
  vely_free (_sql_buf_add_data);

so about 16 ines of code.

This way you can see what actual C code is generated for any Vely code.

And you can also step through this code in gdb by using --c-lines option in vv.

[throwawaymaths]

Maybe you should show more bite-sized simpler examples?

There is a lot going on in your big example, and I wouldn't want to have to download and run it first to get a rough mental model of what's happening.

[dsvr]

I see your point. That's something to add to the documentation. For now, I guess, here it is. Each Vely statement generates some C code, maybe a one-liner, maybe quite a few. It works kind of like a declarative statement, SQL comes to mind. Some clauses in a Vely statement are input data, others are output. The generated code will take the input and fill in the output.

And Vely generates a request dispatcher, which takes the "req" input parameter, which is really the name of the source Vely file. So if "req=mycode", then the function "void mycode()" will execute and it must always be defined in source file mycode.v. This makes it easy to always find the code, and quickly grasp what application does.

Unlike C Makefile, you don't have to write a Makefile. Whatever .v files you have in your source code directory will be automatically picked up and made into an application.

The generated code can and will change. It tries to do the best job of doing what is instructed to do. So if you say:

  web-call "http://website.com" response resp response-code rc status len post files "file1"="uploadtest", "file23"="fileup4"

then it will generate the C code to effectively POST a form to website.com that sends two local files to that server, and will get you the response code and status back. You can do this by using CURL library, but it will take quite a bit of C coding to do this. And there are many different combinations and things you can do, and the code gets generated to do it quickly and efficiently.

The same goes for exec-program, run-query, send-file, encrypt-data etc etc. All this things you can program yourself in C, but these statements are flexible and will let you quickly and safely do those things. More like "what I want to do" rather than "how I want to do it". Though, like I said, you can examine the generated C code to see exactly how it's done.

The "hello world" tutorial is good for this. And if you do decide to try Vely, I would say try

  https://vely.dev/123_hello_world.html

first, as it can't get any simpler. It's designed to give you an application in minutes. You'll get a command-line executable, and you will be running your own application server that can take input from Apache or Nginx via FastCGI. The example though uses FastCGI command line client so you don't have to do anything beyond what's already included in Vely package.

[throwawaymaths]

This description as is should be on the front page.

[dsvr]

I've incorporated it in "In a nutshell" section on the front page. Hope it helps people get what Vely does right away.

[dsvr]

Thank you for this feedback. I really appreciate it. I will incorporate it prominently on the web site.

[dsvr]

Figured out on the fly hackernews markdown. Pretty neat.