- Gpc - gnu.de

Solver
by Cyelee Kulkarni 05 Apr '03

05 Apr '03

I'm using solver to integrate three eqautions. I want the output as a list of numerical values... how do I do this?..... Also, I'm having trouble opening files with an .mx extention, is this a common problem and is there any way I can open this file? Thanks! --------------------------------- Do you Yahoo!? Yahoo! Tax Center - File online, calculators, forms, and more

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Operator overloading
by Frank Heckenbach 05 Apr '03

05 Apr '03

Up to now, GPC supports overloading of binary operators like `+' and user-defined operators such as `Foo', but also only as binary operators. I propose to extend and generalize this mechanism, e.g. to unary operators. Besides the usual unary operators like `+' and `-', you can define your address operator as `@' (BP compatible) or `&' (like in C) or whatever you prefer. Also other C operators like `++' can then be easily defined without the need to have them built-in. A special case would be the `^' operator since it's used both prefix (in pointer type definitions) and postfix (in pointer dereferences). I'm still thinking about the syntax for the operator declarations, but `operator ^ (...)' and `^ operator (...)' would seem to be the most obvious choices. Some time ago, someone asked for backslash interpretation in string literals. Redefining the `'' (i.e., single quote) operator would make this easy. Also, the BP operators `#' and `^' (as in `^C') for character constants could be defined in a similar way, without messing up the syntax when they're built in. The same applies to BP's `$' for hex integer constants. But, OTOH, friends of the C syntax could define `0x' for hex and, if they like, they could even define the `0' operator for octal constants. Those who've always complained about Pascal's verbosity, could finally define the `{' and `}' operators as `begin' and `end' (preferably after defining the comment operator to `(*', `//' or whatever they prefer). And those who would prefer `;' as a statment terminator (as in C) instead of a statment separator can simply redefine this operator. Back to binary operators, apart from `:=' (as recently requested), also `,' would be a very interesting one. We could have all the interesting properties of this C operator in Pascal. Overloading `[' (for self-made arrays) and `.' (for records/objects) would work like in C++, of course, and can probably be used to implement Delphi-compatible object properties without further compiler support. Perhaps we can even define `class' as an operator (that inherits from `object', and `^') to provide for classes with implicit references. The `_' operator could be defined to be rejected in identifiers in classic Pascal (so we don't need the explicit compiler checks we have now), whereas, e.g., international letters can be allowed in identifiers by defining them as new operators. Overloading the `if' operator could be useful to make a new conditional syntax -- perhaps with `endif' to avoid problems with dangling `else' etc. By overloading `const' to `var' for typed arguments, BP's "typed constants" could be supported without any contortions in the compiler. Finally, overloading the `operator' operator seems very interesting, but I'll have to work out the details. Frank -- Frank Heckenbach, frank(a)g-n-u.de, http://fjf.gnu.de/, 7977168E GPC To-Do list, latest features, fixed bugs: http://www.gnu-pascal.de/todo.html GPC download signing key: 51FF C1F0 1A77 C6C2 4482 4DDC 117A 9773 7F88 1707

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Use of external and attribute keywords
by Dominique Louis 05 Apr '03

05 Apr '03

Hi All, A few of questions 1. When using the "external" keyword in GPC, do you have to specify the "name" keyword or does it default to the function name like in Delphi? 2. When defining function pointers, the Gnu Pascal compiler complains if I specify attribute(cdecl); For example type TSDL_Mixer = function( param1 : PSDL_Sound; param2 : Pointer ) : integer; attribute( cdecl );// <--- I get a compilation error here How do I specify the calling convention of a function pointer in Gnu Pascal? 3. If I have installed the Dev Pascal IDE how do I update to the latest snapshot so that I can start using the new keywords. Thanks, Dominique http://www.DelphiGamer.com := go on, write a game instead;

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attribute const: no warning?
by Eike Lange 04 Apr '03

04 Apr '03

Hi Folks! By Compiling the following program with the given unit, the compiler throws no warning but fails running. program Foo; uses MySQL; begin WriteLn (MySQLOptConnectTimeout); MySQLOptConnectTimeout := 100; WriteLn (MySQLOptConnectTimeout); end. { ======== } unit MySQL; interface var MySQLOptConnectTimeout: Integer; external name '_p_MYSQL_OPT_CONNECT_TIMEOUT'; attribute (const); implementation {$L mysqlc.c, mysqlclient} end. _p_MYSQL_OPT_CONNECT_TIMEOUT is defined as "const int" in a C file. What do I have to do to make GPC throwing at least one warning like "accessing read only variable". BTW: Is mixing of attributes allowed like this: MySQLOptConnectTimeout: Integer; external; attribute (const, name ('_p_MYSQL_OPT_CONNECT_TIMEOUT')); Eike

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Locale Directory
by Eike Lange 03 Apr '03

03 Apr '03

Hi Folks! I'd like to improve the facilities of our `intl' unit which interfaces GNU Gettext. There is one little problem with it: The user of this unit might not know where to install and retrive the locale informations, needed by `BindTextDomain'. * A common place under Unix like systems might be /Executable-Path-Without-Bin/share/locale which is well defined for Linux. * What about DJGPP, MinGW, CygWin, MacOS, ...? Are there common rules to find the locale directory? As a reference source code for this problem, you might want to have a look at `gettextdemo.pas'. Thanks for your help Eike

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Re: gpc-20030323 - compiler crash
by Prof A Olowofoyeku (The African Chief) 31 Mar '03

31 Mar '03

Hi Frank [...] > Never say impossible ... > > program Chief44; > > uses Chief44u; > > type > TMemoStrings = abstract object (TStrings) > end; > > begin > WriteLn ('OK') > end. > > unit Chief44u; > > interface > > type > TStrings = abstract object > procedure foo; abstract; > end; > > implementation > > end. > > --- p/gpc-decl.c.orig Tue Mar 25 13:33:12 2003 > +++ p/gpc-decl.c Wed Mar 26 08:48:09 2003 [...] Unfortunately, while the patch works for the test program that you have created (above), the problem still exists with my code, and I still get precisely the same error as before. I have been trying hard (without success) to reduce the problem to a small program, but I have no idea what to look for, or what could possibly be the matter. Perhaps it could relate to lots and lots of sub-classing? Best regards, The Chief -------- Prof. Abimbola A. Olowofoyeku (The African Chief) web: http://www.bigfoot.com/~african_chief/

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no EOF in untyped files?
by Eike Lange 31 Mar '03

31 Mar '03

Hi Folks! I've problems in one of my programs using untyped files. EOF does not work as expected: program Foo; var f: File; i, v: Integer; begin Assign (f, 'foo.dat'); Rewrite (f, SizeOf (Integer)); v := 101; for i := 0 to 10 do BlockWrite (f, v, 1); Close (f); Reset (f, SizeOf (Integer)); while not EOF (f) do begin BlockRead (f, v, 1); WriteLn (v) end; Close (f) end. The output is _not_ 11 times 101 as expected but six lines garbage. Replacing the while-loop with a for-loop (0 to 10), all works fine. What do I wrong? I'm using gpc 20030323 with gcc 3.2.2 Eike

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Happy Birthday GPC
by Frank Heckenbach 31 Mar '03

31 Mar '03

According to the ChangeLog, Jukka Virtanen started implementing GPC exactly 15 years ago. Time for a little celebration! :-) Frank -- Frank Heckenbach, frank(a)g-n-u.de, http://fjf.gnu.de/, 7977168E GPC To-Do list, latest features, fixed bugs: http://www.gnu-pascal.de/todo.html GPC download signing key: 51FF C1F0 1A77 C6C2 4482 4DDC 117A 9773 7F88 1707

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Re: gpc-20030323 testsuite
by Prof A Olowofoyeku (The African Chief) 27 Mar '03

27 Mar '03

Hi Frank [...] > > "./test_sum" | tee test_summary ./test_run: fatal: > > `--print-needed-options' yields: ./test_run: /mingw/bin/gpc: Invalid > > argument Nothing was run." > > Looks like an installation problem. What happens if you insert > > echo "$PC $PFLAGS --print-needed-options dummy.pas" >&2 > > in test_run before the needed-options stuff, and execute the command > that is shown manually (or from bash)? I get nothing. No errors, no output - just nothing. Looking in the directories in which I am building GPC, I see files called "needed-options" in the p/rts and p/utils directories, of zero bytes in size. I believe that this file has always had zero bytes, but that has not been a problem until now. > Is /mingw/bin/gpc the GPC executable? Yes. Best regards, The Chief -------- Prof. Abimbola A. Olowofoyeku (The African Chief) web: http://www.bigfoot.com/~african_chief/

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memory allocation with gpc
by Mehdi Khaldi 26 Mar '03

26 Mar '03

Hi, I'd like to know if memory allocation routines (ie : New, dispose, etc....) use malloc, free... C routines or if they use their own implementations. Thanks

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