HAC (HAC Ada Compiler) is available on two open-source development sites:
https://hacadacompiler.sourceforge.io/
https://github.com/zertovitch/hac

HAC is a small, quick, open-source Ada compiler, covering a subset of
the Ada language.
Even though the HAC documentation is more or less non-existent, the good
news is that you can use, as a help, Ada books and online documentation
about Ada: HAC does not define a dialect of Ada, only a subset.
A glimpse into the file "src/hac_pack.ads" gives you the currently
available types and subprograms.

The latest additions are:
------------------------

- v.0.06: Text File I/O around File_Type (example below)

- v.0.05: type VString (variable-size string), with various operators
and functions ("&", "*", comparison operators, Element, Length,
Slice, Index, Trim, Image, Integer_Value, Float_Value functions);
system functions (Argument_Count, Argument, Get_Env, Set_Env,
Shell_Execute)

HAC programs are real Ada programs, they can be built by a "serious"
Ada compiler, through the HAC_Pack compatibility package.
See the exm/hac_exm.gpr and test/hac_test.gpr project files
for the GNAT compiler.

HAC is itself programmed in Ada. To build HAC for the command-line,
all you need (with GNAT) is to run "gprbuild -p -P hac".
Then you get the executable hax[.exe].
The command "hax" alone will show you basic help.

HAX: command-line compilation and execution for HAC (HAC Ada Compiler)
Compiler version: 0.06 dated 18-May-2020.
URL: https://hacadacompiler.sourceforge.io/

Usage: hax [options] main.adb [command-line parameters for main]

Options: -h : this help
-v, v1 : verbose
-v2 : very verbose
-a : assembler output
-d : dump compiler information

Enjoy
_________________________
Gautier's Ada programming
http://gautiersblog.blogspot.com/search/label/Ada
NB: follow the above link for a valid e-mail address
__
PS: The example (exm/file_copy.adb):

with HAC_Pack; use HAC_Pack;

procedure File_Copy is
s : VString;
f1, f2 : File_Type;
begin
Open (f1, "file_copy.adb");
Create (f2, "file_copy.txt");
while not End_Of_File (f1) loop
Get_Line (f1, s);
Put_Line (f2, s);
end loop;
Close (f1);
Close (f2);
end File_Copy

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