Grawlix

This is the horrible Grawlix Programming Language - created by User:DMC with the intent of introducing enhancements to brainfuck that still uphold it's spirit.

grawlix – Cartoonist's term for random symbols and punctuation used to represent swearing.

Description

• 8 bit memory cells (or other bit amounts)
• Everything initialized to zero
• Cell values rollover
• Program memory infinite
• Data memory infinite
• Stack memory infinite
• T - top of stack
• P - data pointer
• (P) - byte value at P
• P < 0 is an error and should halt the program
• Pop when T = 0 is an error and should halt the program
• A program with only > < + - , . [ ] is Brainfuck, not Grawlix
• The Grawlix interpreter can be used as a Brainfuck interpreter
• Turing complete: yes, because Brainfuck is Turing complete

Enhancements to brainfuck

• Stack operations
• Decimal I/O
• Another loop structure
• Multiply / divide by two
• Functions

Functions

• Function definition '{ code }' can be anywhere in the program listing
• Function definition in program listing '{' is skipped to command after matching '}'
• Only function call '@' runs function code
• To call a function: push function number onto stack, call function with '@'
• The function number is determined by program parsing in the order it is encountered, starting with zero
• 256 functions allowed

Program parsing

• Bracket integrity check
• Parenthesis integrity check
• Brace integrity check
• Tabulate open/close brackets
• Tabulate open/close parenthesis
• Tabulate function locations

Brainfuck commands

><+-,.[]

Grawlix Commands

Command	Description
:	Push (P)
;	Pop (P)
?	(P) = input decimal number mod 256
(	Proceed to next command after ‘(‘ if (P) == 0, the opposite of brainfuck
)	Return to matching '('
{	Begin function definition
}	End function definition
@	Function call: function number previously pushed onto the stack, performs a pop operation
/	Shift (P) right: zero > 7 > 6 > 5 > 4 > 3 > 2 > 1 > 0 > null
|	Shift (P) left: null < 7 < 6 < 5 < 4 < 3 < 2 < 1 < 0 < zero
=	Print out (P) as a zero-filled three digit decimal number
^	Halt

Some possible code constructs

Code schematic	Explanation
____	some code
{_______}	a function definition
{___@___}	a function call inside a function definition
{_____}__{________}___	two function definitions
{___{____}__}	possible but unnecessary function definitions
__{_0__}__{__1__}{_2__}	+:@ push 1,call function 1
__[___]_(_____)__	loops
__[___(___]___)__	a possible loop structure, not a syntax error, unknown if it can be made to do something useful

Examples

Hello World!\n

+|||+|||.>+++|||+||+.+++++++..+++.>+|||
||.>+|||+++|||-.<<.+++.------.--------.
>+.>>+||+|.

Fibonacci

correct until an 8-bit rollover occurs

>>+||+|<+<=>[>.<=:<[>+<-];>]!

Truth-machine

:+:?(;;=^);[=]

External resources

• Grawlix Programming Language – Interpreter written in Python 3