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=={{header|Brainf***}}==
See syntax [http://ninh.nl/blog/2008/10/25/brainfck-birds-of-a-feather-session-take-2/ p.4 BNF BrainF*** Syntax]
<div style="height:30ex;overflow:scroll"><pre>
! ---------------------------------------------------------------------------
!
! Brainf***
!
!
! As legend states, the Brainf*** Programming Language (also called BF by
! those not wanting to curse) was created by Urban Mueller in 1993.
! The language was designed, in part, so Mueller could create the smallest
! compiler ever. The first BF compiler was written for the Commodore Amiga
! OS 2.0 and was only 240 bytes in size.
!
! BF is a Turing-complete language. This means that any BF program can be
! proved to be equivalent to a Turing Machine.
!
! The system consists of an continuous array of 30,000 bytes (more can be
! added of course, but this is the standard size). Each cell is accessed
! through a single, global, pointer that can either move forward or backward
! on the array. The content of each cell can be modified by either reading a
! new byte from standard input or by incrementing or decrementing the
! current value. The array is initialized with zeroes.
!
!
! The BF Programming Language only consists of 8 different instructions:
!
! > Increment the pointer
! < Decrement the pointer
!
! + Add 1 to the current cell
! - Substract 1 from current cell
!
! . Print the current cell to the screen using its ASCII value.
! , Read a character and store its ASCII value in the current cell
!
! [ Jump forward past the corresponding ] if the current byte is zero
! ] Jump back to the statement after the corresponding [ if the
! current cell is not zero.
!
! In reality, the BF Programming Language is not that different from ANSI C.
! Each of the 8 instructions can be substituted for C statements and
! language constructs.
!
! > becomes p++;
! < becomes p--;
! + becomes *p++;
! - becomes *p--;
! . becomes putchar(*p);
! , becomes *p = getchar();
!
! [ becomes while (*p) { ...
! ] becomes }
!
!
! BF also treats all characters that are not the 8 basic commands as
! comments. In the grammar below, Whitespace is defined to include all the
! printable characters - with the exception of the statements.
!
! Please see http://en.wikipedia.org/wiki/Brainfuck for more information
!
! PLEASE NOTE: This grammar was created for fun. If you want to create a BF
! parser, it is far easier (and much more efficient) to write
! one manually.
!
! ---------------------------------------------------------------------------
"Name" = 'Brainf***'
"Author" = 'Urban Mueller'
"Version" = '1993'
"About" = 'Brainf*** was created by Urban Mueller with the goal to build'
| 'the smallest compiler ever.'
"Start Symbol" = <Instructions>
! ============================================== Comments
{WS} = {Printable} - [<>+-.,'['']']
Whitespace = {WS}+
! ============================================== Statements
<Instructions> ::= <Instructions> <Instruction>
|
<Instruction> ::= '>' ! Increment p
| '<' ! Decrement p
| '+' ! Increment a[p]
| '-' ! Decrement a[p]
| '.' ! Output a[p]
| ',' ! Input a[p]
| '[' <Instructions> ']'
</pre></div>
=={{header|C}}==
The Syntax follows, [http://c.comsci.us/syntax/index.html C Syntax]
|