Malbolge

Malbolge ( /mælˈboʊldʒ/ ) is a public domain esoteric programming language developed by Ben Olmstead in 1998. It was named after the eighth circle of hell in The Divine Comedy, written by Dante.

Malbolge is peculiar in that it was designed to be the most difficult language, through a 'crazy operation' counterintuitive, base-three arithmetic, and self-altering code. However, many of the tricks used to make it difficult to understand can be avoided and useful programs built on it.

Programming in Malbolge

Malbolge was very difficult to understand when he arrived. Two years passed before Malbolge's first program appeared. The author himself has never written a Malbolge program. The first program was not written by a human being; it was generated by a beam-seeking algorithm designed by Andrew Cooke and implemented in Lisp.

Later, Lou Scheffer published a cryptanalysis of Malbolge and provided a program for copying its input to its output. He also saved the original interpreter and specification after the original site went down, and offered a general strategy for writing programs in Malbolge, as well as some thoughts on his Turing integrity.

Olmstead believed that Malbolge was a linearly bounded automaton. There is a discussion about whether sensible loops can be implemented in Malbolge; many years passed before the first without termination was introduced. A correct 99 Bottles of Beer program dealing with loops and non-trivial conditions was not announced for seven years; the first correct one was by Hisashi Iizawa in 2005. Hisashi Iizawa et al. He also proposed a guide to Malbolge programming for the purpose of obfuscation for software protection.

In 2020, GitHub user kspalaiologos created a working Lisp interpreter in Malbolge Unshackled.

Example

Hello World sample code:

 (= tax`$9]7 tax5YXz7wT.3,+O/o'K%$H"'~DATA#z@b=`{^Lx8%$Xmrkpohm-kNi;gsedcba`_^][ZYXWVUTSRQPONMLKJIHGFEDCBA@?g= tax;:9876543s+O.

Echo program

This program reads a string from a user and prints that string, similar to Unix echo

(=BA#9"= tax;:3y7x54-21q/p-,+*)"!h%B0/.
~ P
Δ:(8 fake
66#
gJ%