josephoziel / legend

An esolang based on legendre symbols.

An esolang based on legendre symbols. This language is heavily based off of Kak.

Example

The file hello_world.leg contains a possibile hello world in Legend.

(Image to show the program with text wrapping)

When compiled it produces a binary string:

$ legend.exe hello_world.leg
010010000110010101101100011011000110111100101100001000000101011101101111011100100110110001100100001000010

SIDE NOTE: The program hello_gen.py was used this generate this program randomly. It was not written by hand.

If you split this binary string into octals, it forms the ASCII text Hello, World!.

Proof:

Spec

Lexer

The lexer only accepts the following characters: (, /, ), 0-9.

No other characters such as whitespace or alphabetic letters are allowed.

Semantics

A Legend program consists of n legendre symbols of the form (a/p) where a is some positive number and p is an odd prime.

RULE: every legenrdre symbol must be different or else it will fail.

Each legendre symbol evaluates to 0, 1 or -1. Each value corresponds to some instructions:

Value	Instruction
-1	Move the pointer to the right and flip the bit at the new location
1	Move the pointer to the left if the pointer index is greater than one (1)
0	Skip the next instruction if the current cell's bit is zero (0)

Thus, every program structure has infinitely many implementations.

In addition, once the interpreter reaches the last legendre symbol, it tests whether the current cell is 0. If it is, it stops execution, and if not, it executes the instructions again. (It also prints the current tape at the end of each iteration).

Use

The interpreter lies in i.pl (it's golfed by the way).

To run a program: legend.exe program.leg

Windows

Go into the directory and run this command: swipl -o legend.exe -c i.pl --goal=main. Now you will have a legend.exe which you can use like this: legend.exe program.leg.