disd@hubcap.UUCP (Gary R. Heffelfinger) (01/29/88)
I have just discovered DRACO, the curious language written by a professional compiler writer in his off hours. (Forgive me, but his name escapes me.) Are there any experienced DRACO users (Draconians?) on the net? Does the compiler's author have access to it? I've been writing some programs in it over the last few evenings and I admit that I like its feel. Consider, though, that I've been spending far too much time spinning my wheels with TDI Modula-2, so just about any working compiler that doesn't steal my precious memory would be refreshing. :-) The author has provided resonably good documentation and lots of code samples to read, so I'm not really looking for that kind of information. What I'd really like to know is, are there any vicious bugs I should be aware of? The simple Intuition programs I've attempted have worked like a charm, but I haven't gone very deep and I certainly haven't written any long code. I'd also like to get a feel for whether or not the author is still working with it. In his docs he mentioned that he was working on a Amiga version of his DRACO linker. I believe he also mentioned some REAL variable support. (Don't really need it much but it's nice to have it when I do need it.) The bottom line is that it impresses me enough that I'd be willing to send the author some $$'s for his work, assuming that he hasn't completely abandoned work on it. -- Gary R. Heffelfinger Employed by, but not the disd@hubcap.clemson.edu mouthpiece of, Clemson University "If you prick me, do I not...leek?" - Data
cg@myrias.UUCP (Chris Gray) (02/03/88)
Draco is still alive and well. There are a few users around town here (Edmonton
Alberta - the frozen north), plus scattered others down in the US of A. There
could also be lots more that I don't know about. As for its current status
with me:
- I use it for all of my programming on the Amiga
- since the Draco distribution (Fish disks 76 and 77), I've been busy
working on:
- Amiga Empire (a full rewrite of UNIX Empire) - Fish disk 118?
- a Canadian content screen hack (coming soon!)
- IFF stuff (showILBM with colour cycling)
- a truly overkill expansion of my terrain generator, including
a colour palette editor requester, a file requester, and a
library to ease text menu creation
- the Amiga port of my graphics D & D game system. This involved
about 4K lines of new code (View, moving Viewports, input.device
handler, mouse handling, a sprite, etc. along with a whole new
polygon-fill picture editor (to be scrapped, sigh))
- small start (the lexical analyzer) for Draco-II (don't hold
your breath!)
As for bugs, well there are some that have shown up, but none have been
serious enough to merit a redistribution. Here's the complete list as far
as I know (if anybody knows of any others, PLEASE let me know!):
- the result of an I/O operation (like read, writeln, etc.) returns a value
(internally called an IORESULT) which is boolean if used, but can be
ignored without a message from the compiler. Currently you can't use
one of these as the return value of a procedure. (Probably a 5 line fix.)
- Can't currently predeclare a function with a parameter which is an
array of unknown size. E.g. the compiler won't accept
extern func([*] int param)int;
...
proc func([*] int param)int:
...
corp;
- bad code is generated for a construct like this:
if (x = 'a') ~= (y = 'a') then
...
I probably forgot to call "putInReg" for the left-hand-side expression
for a comparison of booleans.
- include/devices/timer.g change UINT -> UNIT
include/exec/interrupts.g parameter of "Cause" in "*Interrupt_t"
include/exec/interrupts.g is_data -> is_Data
include/intuition/gadget.g added union types instead of *byte
a few other minor changes to obscure include files
- the compiler uses a shift right to do a signed integer divide by a
constant power of 2. This doesn't work. Oops!
The last two are the only ones I've bothered to fix.
--
Chris Gray Myrias Research, Edmonton +1 403 428 1616
{uunet!mnetor,ubc-vision,watmath,vax135}!alberta!myrias!cgmartens@CIS.OHIO-STATE.EDU (Jeff Martens) (12/02/89)
In article <0847.AA0847@ami-cg> Chris Gray (mail to whom bounces) writes: >The answer of course is that you shouldn't BUY any compiler; you should just >trot on down to your nearest Amiga user's group (or decent software store) and >pick up copies of Fish Disks #76, 77 and 201. (Should be available for the >cost of the disks + copying.) They will provide you with a full distribution >of my Draco compiler/system for the Amiga. Code compiled with the compiler on >Fish #201 will execute almost as fast (with 10% in most cases, I'd say) as >that generated by any of the commercial compilers. The language also provides >strong type checking, which can be an immense boon to someone just starting >out with Amiga programming, something which C and Fortran don't do. All of >the languages (except, likely, Fortran) provide essentially the same features, >so graphics programming will be much the same in any of them. I've done a >number of graphics programs in Draco, and I've seen others done by happy >users elsewhere. >Given the price, (free), its a good way to find out if your really do want >to get into this Amiga programing stuff! >P.S. There will be a third version of the compiler coming out in the future, >as soon as I finish with Amiga Empire V2.0 . So far I've added global register >variables (real useful for shared libraries) and data initializations like >those in C. >Chris Gray usenet: {uunet,alberta}!myrias!ami-cg!cg CIS: 74007,1165 It seems that I've heard of Draco somewhere along the way, but really know nothing about it. So, for people in my situation -- ignorant of Draco, spiteful of C, and too cheap to buy a Modula-2 compiler -- maybe you could post a quick description of Draco. Also, you suggested that we pick up 3 Fish disks. Am I correct in guessing that really FF201 is enough? Or would I really want all three? Thanks. Does Draco per chance run on a Sun 3 Berkeley Unix system? In the best of possible worlds, I'd just be using one language. -- Jeff (martens@cis.ohio-state.edu) With the 11/89 issue, the Communications of the ACM has finally become 100% devoid of computer science.
cg@ami-cg.UUCP (Chris Gray) (12/08/89)
In <8912020143.AA10404@dinghy.cis.ohio-state.edu> martens@tut.cis.ohio-state.edu writes: >It seems that I've heard of Draco somewhere along the way, but really >know nothing about it. So, for people in my situation -- ignorant of >Draco, spiteful of C, and too cheap to buy a Modula-2 compiler -- >maybe you could post a quick description of Draco. > >Also, you suggested that we pick up 3 Fish disks. Am I correct in >guessing that really FF201 is enough? Or would I really want all >three? Thanks. > >Does Draco per chance run on a Sun 3 Berkeley Unix system? In the >best of possible worlds, I'd just be using one language. Glad to oblige! I describe Draco as a language with semantics similar to C (but more strongly typed) and syntax similar to Algol68 (but much less ambiguous at the syntactic level). The compiler is complete, comes with a full I/O and utility library, comes with a full set of include files for the Amiga, and comes with a number of other utility programs. It compiles fast, but still generates fairly good code. The only commercial compiler I've got is Lattice V4.0, and Draco compares well with it (files are much smaller, compiles much faster, and code runs about the same speed/size). Holding to the maxim that a picture is worth a thousand words, here's a silly little Draco program that compiles and runs: #drinc:intuition/miscellaneous.g #drinc:intuition/screen.g #drinc:intuition/window.g #drinc:graphics/gfx.g #drinc:graphics/rastport.g #drinc:libraries/dos.g uint WINDOW_WIDTH = 500, WINDOW_HEIGHT = 150; proc process(register *RastPort_t rp)void: register ulong i, j; for i from 0 upto WINDOW_WIDTH - 1 do for j from 0 upto WINDOW_HEIGHT - 1 do SetAPen(rp, if i > j then (i - j) % 4 else (i + j) % 4 fi); ignore WritePixel(rp, i + 2, j + 10); od; od; Delay(50 * 20); corp; proc main()void: *Window_t window; if OpenGraphicsLibrary(0) ~= nil then if OpenIntuitionLibrary(0) ~= nil then window := OpenWindow(&NewWindow_t( 100, 50, WINDOW_WIDTH + 4, WINDOW_HEIGHT + 12, FREEPEN, FREEPEN, 0x0, WINDOWDEPTH + WINDOWDRAG + SMART_REFRESH, nil, nil, nil, nil, nil, 0, 0, 0, 0, WBENCHSCREEN)); if window ~= nil then process(window*.w_RPort); CloseWindow(window); fi; CloseIntuitionLibrary(); fi; CloseGraphicsLibrary(); fi; corp; It opens a window on the workbench screen, draws a kind of moire pattern into it, waits 20 seconds, then exits. I compiled it by typing: draco sample and linked it by typing dr1lib2 intuition graphics sample to produce a 5100 byte object file (which, because I was lazy, mostly consists of some of the Draco I/O library, and some symbolic information that I had hanging around in my standard libraries). If I give it the '-v' flag, it tells me that the first routine was actually 120 bytes, and the second was 140. To reply to Jeff's specific questions: At a minimum you need Fish Disks 77 and 201. 77 contains all the documentation and a bunch of samples. 201 contains the latest released version of the compiler, include files, libraries, scripts, tools, etc. 76 has info, etc. on how to install the compiler, but you can probably do without it. Draco doesn't YET run on a Sun, but I've been meaning to port it for about 2 years now. Mostly so I can port my editor so I don't have to wait 10 seconds for emacs to page in and echo what I've typed on my Sun at work. I've got some time off between Christmas and New-Years - maybe then... Note, however, that a Sun version wouldn't automagically have all of the C libraries available. It would have its I/O system (replaces stdio), and interfaces to the system. There IS a kludge to make the compiler generate C-style calls, but you have to reverse the function arguments, so that's a pain. -- -- Chris Gray usenet: {uunet,alberta}!myrias!ami-cg!cg CIS: 74007,1165