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I am interested in making my own programming language on top of C, but I have no
idea where to start.
So, I researched, this caught my attention:
A lot of languages are C-based.
Popular programming languages like C++ and Objective-C, and possibly C# and Java are all built on top of C. (Not to mention Python)
How did C++ and Objective-C creators managed to make a new language that is C based, but add object oriented programming concept added?
C based does not neccesarally mean that it's interoperable with c. It can just mean, that it uses the same paradigm or similar syntax like egyptian bracets.
Java is C based but also borrows from Smalltalk and it cannot run any of C code. C++ can call C functions because it's compiler produces the same binary code as C code. Once you have linked their binaries they become interoperable. Pythons implementation CPython does not produce any binaries first, it's an interpreted implementation, meaning it is run by an interpreter Programm which holds the whole parsed syntax tree in memory. And because the Interpreter is just a C programm itself, it can call other C functions. So there is no such thing like adding features in top of C. Those are different languages, with differen compilers/interpreters and grammatics which just borrow some of the grammatical rules from c.
The easiest way to start creating an own language, is by using a parser generator like antlr. And i would start creating an interpreter and not a binary compiler. Perhaps a compiler, which compiles to c. Knowledge about language grammatics is essential.
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I'm looking for some kind of C dialect that is as minimalistic as C but has built-in classes support. So I can (and encouraged to) use macros, pointers to arrays and manual memory management but also create classes, add fields and member functions to them etc. This question appeared when I tried to implement some kind of OOP in C and typedef struct and function pointers do something similar to what I want, but "member functions" require to manually pass a pointer to the object as a parameter to them, and that's not what I want to do. I know that I can just write on C++ as on "C with classes" and I would, however C++ encourages a different programming style and I'm curious if there is something that is exactly what I want.
I was searching for "C with classes" but I've only seen C++ in results, so I expect that the answer is "just use C++" and I'm OK with that, but I'm just curious.
C++ encourages a different programming style
You can write C++ in whatever style you like. Just choose not to use the features (and libraries) that don't suit your C-with-classes aesthetic.
"C with classes" was originally compiled to C by Cfront, but that's extremely dead AFAIK.
I doubt there's much demand for a resurrected Cfront when simply choosing a subset of C++, and using a current C++ compiler, already does everything you actually require.
FWIW I have written object-oriented C in the past, and manually passing this isn't that much of a burden. Even in Python you have to declare the self parameter explicitly, and nobody seems upset about that. Having to pass it in explicitly as well isn't so bad.
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I am new to C and I use to code in python, and I usually print too much variables and text to test my code and printf statement is irritating sometimes. I want to write a function in c which works exactly like print function in python.
I am facing two problem while writing the function.
I want to take n number of arguments as input to the function.
I want to take any data type as input to the function,
for Eg: print(12); print("hello"); print(123.12) should not raise error.
What have I done so Far
I found solution for taking n number of arguments using <stdarg.h>, but I have to specify the data type of the first argument which is not what I want.
"generic selection" Macros can be used to call different function on different data type of argument passed but not sure how it can be done, here is the link which I used for reference.
I want to write a function in c which works exactly like print function in python.
You simply cannot do that (because of type erasure : at runtime, type information is lost in C). Read Modern C then see this C reference.
In practice, you'll better write one function per datatype in C to print it. So it would be void print_int(int); to print an integer, void print_double(double); to print a double, etc. Once you have a collection of such functions you might use _Generic inside a macro (but that is rarely useful; it can handle a finite set of types).
Study for inspiration the source code of existing open source C software on github or elsewhere. Look for inspiration inside the source code of GNU bash, sqlite, GTK or GNU bison (and perhaps inside the source code of Python; half of the Python interpreter is coded in C)
Read also the documentation of your C compiler, e.g. GCC. So compile with all warnings and debug info: gcc -Wall -Wextra -g then use the GDB debugger.
Perhaps you want to implement some tagged union abstract data type in C. Then take inspiration from GNU guile or the runtime of Ocaml and dive inside their source code.
Once you are more familiar with C, read some C draft standard, e.g. n2176
Consider using Frama-C or the Clang static analyzer.
Consider also sometimes generating some C code, like SWIG does.
Budget weeks of work.
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How was the first compiler written?
I'm asking this as a single question because, essentially what I'm trying to ask is at the bottom how is all of this implemented, here goes:
How was the first C compiler generated, since C compiler is written in C itself then how was the first source of C compiler generated?
Is C written in ASM, how are languages actually designed?, because before we had high level languages the only way to design something was through ASM, even if C is derived from earlier languages, how were they designed? (My clue is ASM)
I'm getting confused as to how does C work down at the bottom. What I'm trying to say is since at the bottom, everything is implemented at the processor by OPcodes. So what my understanding was that C programs are "essentially" translated to Sys Calls which are implemented by the Kernel.
But then how are syscalls implemented? (Do they directly correspond to OPcodes or is there any other layer of abstraction.
How was the first C compiler generated, since C compiler is written in C itself then how was the first source of C compiler generated?
Bootstrapping.
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How to code a compiler in C?
How would I start writing a compiler from scratch (no Flex or Bison or Lex or Yacc) in C? I have a language that I wrote an interpreter for, and it's kind of like Forth. Sort of. It takes in symbols and interprets them one at a time, using a stack.
How would I make a compiler?
That wasn't a particularly spammy bit; just to show people the syntax and simplicity.
http://github.com/tekknolagi/StackBased
Simple!
You tokenize the input.
You build a proper representation of it, generally this is an Abstract Syntax Tree, but that is not required.
You perform any tree transformations you may require (optional).
You generate the code by walking the tree.
You link any disparate portions together (optional)
Flex and Bison help with stage 1 and 2, everything else is up to you. If you're still stuck, I suggest going through "Programming Language Pragmatics" or The Dragon Book.
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It seems that are several ways to call matlab in C C++ and to call C C++ in matlab. While I try to list them here, please point it out If I miss something.
To call C C++ in matlab, there are also two methods. The first one is to call functions in C shared libraries. The second one is to build C C++ code into binary MEX-files, which will be called from the MATLAB command line. For the first method, are the C shared libraries are just general ones, i.e. without change to their C code for matlab and compiled from general C compiler like gcc?
To call matlab code in C C++, there are two methods available. The first one is Matlab engine. The second one is to use MATLAB Compiler mcc to create C or C++ shared libraries from your MATLAB code.
Besides matlab and C C++ can communicate via writing and reading data to and from some file (e.g. mat file, text file).
Having more than one ways to accomplish each of the goals here, could you tell me what cases are best for using which of them? i.e. calling functions in C shared libraries VS building C C++ code into binary MEX-files, Matlab engine VS compiling Matlab code into C C++ shared library.
Thanks and regards!
I only have expreience with calling C or C++ functions from MATLAB. It looks to me like the only difference between calling functions in a shared library and calling functions from a MEX file is that with a shared library, you have to call the function with 'calllib' which is a command line type function and MEX functions allow you to call functions as if they are built-in functions so the interface is a little cleaner.
My suggestion is to use MEX files if
You are using C++ (you may have to write a wrapper to use a C++ in a shared library)
You are using MATLAB as the glue for a large number of optimized C or C++ routines. You'll want to be able to call them cleanly.
Use shared library if
You already have an existing C library that can be used without modification.
You only need a small number of calls to C functions.
Really, it comes down to the interface. I personally prefer the MEX file route because it provides the cleanest interface from MATLAB to your C or C++ function. You can call it like just another function with standard MATLAB types. With a shared library, you may have to do some data formatting before calling the library function
I think the methods you've named are correct (it's been a while since I've used them)
The matlab C-compiler isn't really special; it is possible to use different compilers. See link list of supported compilers. This does not include gcc, but MS Visual studio is included. You'll run into issues when linking with the supplied libraries.
Basically: calling matlab from C is something you'd do if you need a tight interface; for instance if you want to synchronise 2 tools, or your S-function (simulink) requires additional information. But then, such a file is propably called by Matlab/simulink in the first place.
Calling c from matlab is what you want to do if you write your own S-functions or extensions to matlab.
The choice between C and C++ is yours; if you start from a blank sheet I suggest you use C++; you don't need to use the complete functionality but it allows more freedom. Also more libraries tend to be available for C++ nowadays.
C is the language of choice if you need to migrate to very different environments; i.e. to compile C to DSPs for instance. Or if you have got legacy code in C to start from. Mixing C and C++ is possible, but a can be a bit cumbersome; I'm sure you'll find topics on StackOverflow on this subject alone.