The smallest translator you've ever seen

This morning I wrote a brainf**k c translator. It took me about an hour in total.

The entire content is less than 50 lines of c code. You can see it here.

What is brainf**k?

This is a profound encoding language. Invented by Swiss students in 1993, it is almost considered the minimum requirement for Turing completeness.

It is also one of the most famous Essolan languages ​​in existence.

The syntax is extremely simple: there are only 8 characters, and the rest will be ignored.

 > [-]<.> [-]> [-] [-]>> [-]<p>Guess what it does. Guess it.</p>
<p> This is a Hello world! programme.</p>
<p> Essentially, in brainf**k you get an array of 30000 bytes and a cursor. You can use > and  Print the value of the current cell</p>
<pre class="brush:php;toolbar:false"> > ; increments cursor position
<p>It's almost everything about brainf**k.<br> I've written more functional programs before in <em>assembly</em> .</p><h2 id="Why-Just-why"> Why? Just why?</h2><p> I wrote this compiler completely because I was bored and I found a lot of interpreters so I think the world needs a brainf**k compiler.</p><blockquote><p> Nevertheless, there is no denying that if you want a very good brainf**k compiler, check out this one.</p></blockquote><h3 id="Why-c"> Why c?</h3><p> Many reasons:</p>

• I want more practice
• Very fast
• It's mainly portable
• Very common
• Anyway, I don't need much code.

The last reason: integer overflow. Often, this is a bad thing that people hate. This may be the reason why unit testing is invented (uh). But brainf**k is different. The upper limit of the number in the memory tape is 255, and if it exceeds this, it should be reset to 0. Also, if the value is below 0, it should be reset to 255. c will do this on its own; I don't need to write any code for it.

how?

A higher level overview:

• Read code from file or standard input to memory
• Convert each character to c code
• Printed c code.

It reads brainf**k code from the file into code[].

Then, it sets up a basic C program:

 #include <stdio.h>
int main() {char t[30000]={0};int p=0;
</stdio.h>

You may have noticed that it lacks the closing bracket. That's because more code is added to the char[].

If you want to know, char t[30000] is the memory given to you. I use t as the abbreviation of the tape, but shorten it because these programs are not suitable for human readability.

Next, it loops through the code array, which is an array of single characters. For each character, it converts it to c code:

character	Becomes
>	p
	p--
-	t[p]--
	t[p]
.	putchar(t[p])
,	t[p]=getchar()
[	while(t[p] != 0)
]	}

You can check out the above to see what these symbols do.

These values ​​will be added to the program output, which will contain valid c code.

Finally, add this code to the final output:

 return 0;}

The output program ends here. The translator then prints this code to standard output so that the user can operate as he wishes.

The final thought

I have some ideas for improvement while writing this post. I don't think I can do too many things to make it faster, but I can do something to make it safer and better.

You can view the final code here.

You can also make any kind of contribution if you wish.

Thank you for reading!

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