Alphabet Stew

Brainfuck derivative using only letters (a – z) Created by User:DMC

Concept

• A stack based esoteric programming language with exactly 26 commands
• Each command is represented by a single character [a - z]
• Numbers [0 - 9] are not used
• Any character not within the set [a-z] is ignored
• whitespace may be used for clarity

Description

• an infinite array of cells
• all memory is initialized to zero
• commands that require two values to be pushed will pop two values and push the result onto the stack
• commands that operate on one cell do not use the stack
• '!' diagnostic command to print out memory cells up to highest value of the data pointer, does not have to be implemented
• no effort was made to assign commands to any particular letter

Instruction	Operation	Explanation
a	shift right	current memory
b	.	output ascii
c	peek	top of stack
d	<	p -= 1, p<0 is an error
e	+	increment memory
f	jump left	program counter -= current memory
g	add	push two
h	jump right	program counter += current memory
i	]	close loop
j	clear stack	top of stack = zero
k	xor	push two
l	pop	into current memory
m	shift left	current memory
n	halt	program stop
o	push	from current memory
p	and	push two
q	or	push two
r	input decimal	current cell = input mod 256
s	>	p += 1
t	[	open loop
u	-	decrement memory
v	output decimal	three digit zero filled
w	exchange	top two values on the stack
x	subtract	push two
y	not	(p) = not(p)
z	,	input one keypress

Examples

Hello, World!\n

oemmemosemmmmmeoooog
gseogcosemmmogscosee
emogdeeeossemmememmm
uosemmmmmosemmememmo
ddddouuuoouuuuuuuoss
sosogluuuuoltbli!

Fibonacci

First 14 values before it overflows 8 bits

emmmmuuussemmemdvsbdoeodtscvsbdgowdui!

Truth-machine

rtsetviiv

External resources

• Alphabet Stew – Interpreter written in Python 3