hello. gonna start writing a compiler now for a pascal-like language. im thinking of doing it in C. anyone have any tips/suggestions before i start?

how long do you think it would take a reasonably good C programmer to do this?
thanks.

Qdepartment on yahoo.com is a really good forum/group to help with compilers/interpretors, I think in C/C++ only, though I'm sure there must be others there who knows Pascal. Yet everything I've seen so far is only for C/C++.

cool. well, the grammar is similar to pascal. the implementing language can be any.

Learn all you can about Flex and Bison, as they will save you many hours of programming tedium with any reasonably complex language.

I did a couple of compilers for course projects at university. A compiler for a very simple language, written in C++ without the aid of Flex or Bison, took most of a semester to write. Probably 40 or 50 hours went into it; part of it was already written for us. The next semester, I wrote a compiler for a language that was nearly as complex as C is (probably 2 or 3 times as complicated as the language used in the previous semester), which, thanks to Flex and Bison, took far less time to write - maybe more like 20 hours to finish, once I understood how to do it.

hey wapcaplet - thanks.
i did write a scanner using flex/bison.
are u saying that you had a compiler from scanner to code generator done in ~20 hours in total?
i think im startin to feel ill now. i'll now downgrade "reasonably good C programmer" to something else.

Yacc is a pretty good tool as well. If you get the right set of tools all you really need to make your own little compiler is a good grammer. I did a compiler project in college for a simple language kind of like lisp (hey... it was an assignment) and once I had a good understanding of lex and yacc I got it working in about 10 hours. Of course the grammer was really simple so that is partially why it took so little time. That and the fact the language really was useless.

Perl was designed in Lex and Yacc so they must be good for something.

10 hours? ill go kill myself now.

You could probably accomplish it in less than 10 hours if you've done it a few times before, or if you don't care about it actually working

10 hours? for my mother. for me 2-3 hours.



kiddin' lol

From what I understand, Bison is just the GNU implementation of yacc.

If you are doing it for a college project you can use the any language and I prefer C or C++ for the first time people because there is much docs about it and implementations as well so you can learn by example (memory mapping!) and if you are doing it for business (only you can calculate its outcome/income!).

its for college. and ill be doing it in C. hope to start on it soon.

while bison, yacc, and flex are indeed great tools for getting compilers written faster, imo, there's still something to be said about the nitty gritty theory on creating a language especially if your prof, like mine, won't allow you to use those tools.

great for reference at least.

http://www.amazon.com/exec/obidos/tg...57424?v=glance

Well, language design and language implementation are two entirely different things. All bison and flex do is automate the fairly simple (but all too time-consuming) task of writing a parser for the language. You still have to design the language properly, write the code-generation stuff yourself as well as the optimizer if you're going to have one, etc. The hard part you still have to do yourself.

Also, if the design of the language is what you want to concentrate on first (which you should if you're developing a serious language rather than a toy language so you can concentrate on the compiler), check out this:
http://www.nondot.org/sabre/Mirrored/AdvProgLangDesign/