tbf

tbf is a language that can be used to write Brainfuck programs in a simpler way. Programs written in tbf are compiled to Brainfuck, where they then can be compiled using any BF compiler.

Syntax

tbf includes the following constructs:

General:

• Everything is case insensitive (“hello” is the same as “Hello” as “HELLO” etc)
• Every command has to end with a ”;”
• You can do comments by using ”%” to start a comment. The comment will end at the end of the line (as in Bash for example).
• All new identifiers (variables) will be automatically allocated and initialized as zero.

Basic commands:

• “moveto <identifier>;” moves the tape at the place designed by <identifier>
• “inc;” increment the current position
• “dec;” decrement the current position
• “put;” output the current position as a character on the screen
• “get;” read a character from keyboard into the current position
• “zero;” set the current position to zero
• “print;” output the string that starts at the current position (yes tbf has strings. I'll get into more detail later)
• “Add <identifier>” adds the value stored at <identifier> to the current cell. Be carefull, there still might be a bug that makes your program go into an infinite loop when you add an identifier to itself. I meant to fix it, nut I am not sure if I ever did.
• “Sub <identifier>” similar to add, but does subtraction
• “Store <identifier>” store the value that is designated by <identifier> at a the current position
• “Retrieve <identifier>” restore the value of an <identifier> from the current cell

Identifier can consist of the following:

• names of variables in the form [A-Z a-z _][A-Z a-z _ 1-9]*
• integer literals (e.g 10, 11, -1234 etc)
• single characters in ' '
• Strings in ” ”
• “new” this identifier always indicates a newly produced value
• ”.” to current position
• ”&<identifier>” yes this works to, take a c-guess what it does

More complex constructs:

• “While <test> do <expr>” Loops. When you enter the loop the tape will point to identifier that was used in the test
• “Begin <expr>;[<expr>;…] end” blocks of code, used to group several instructions
• “declare <identifier> as <identifier>” this introduces an alias for a previously used identifier

Tests:

• “isneg <identifier>” tests whether an identifier is negative
• “ispos <identifier>” tests whether an identifier is positive
• ”<identifier>” tests for zero

Example Programs

Hello World

    moveto "Hello World!\n";
    print;

(Yes, strings are this simple)

Output all chars from 255 backwards

    while 255 do begin
       put;
       dec;
    end 

Cat program

    moveto new;
    inc;
    while . do begin
       get;
       put;
    end

Multiplication of two numbers as a macro

   define mult(a,b) as begin
      zero;
      moveto hlp;
      add a;
      while hlp do begin
         dec;
         moveto mult;
         add b;
      end
   end
   moveto new;
   mult(10,9);
   put;

See also

• ClearBF

External resources

• tbf homepage (from the Wayback Machine; retrieved on 3 November 2016)