amuse

An esoteric programming language based on musical notation.

Building

To build the amuse executable, do the following:

$ cabal configure
$ cabal build

The built executable can be found in dist/build/amuse/ or, alternatively, installed to $HOME/.cabal/bin/ with:

$ cabal install

Usage

Amuse works by reading in MIDI files and executing commands based on the note parsed. The following table shows what command corresponds to what note.

Note	Command	Alternate
C	Succ	Pred
C#	InChar	InNum
D	Swap	NOP
D#	LoopBegin	Continue
E	Dup	Over
F	Drop	NOP
F#	LoopEnd	Break
G	Add	Sub
G#	CompareEQ	CompareGT
A	Mult	Div
A#	Alternate	NOP
B	Print	PrintNum

The commands are explained below.

Add

Adds the top two elements of the stack and pushes the result to the stack.

E.g. [2, 3, 4] -> [5, 4]

Alternate

Alternate specifies that the following command should execute its alternate form.

E.g. Alternate + Note C -> Pred

Break

Breaks out of a loop and continues execution past the next LoopEnd.

CompareEQ

CompareEQ checks if the top two stack elements are equal. If true, execution continues normally. Otherwise, execution skips the next instruction.

CompareGT

CompareGT checks if the second element of the stack is greater than the top element of the stack. If true,execution continues normally. Otherwise, execution skips the next instruction.

E.g. [2, 3, 4] -> true

Continue

Continue automatically jumps back to the previous LoopBegin.

Div

Div - Divide - Divides the second element of the stack from the first element of the stack.

E.g. [2, 3, 4] -> [3/2, 4]

Drop

Drops the top element of the stack.

E.g. [2, 3, 4] -> [3, 4]

Dup

Dup - Duplicate - duplicates the top element of the stack.

E.g. [2, 3, 4] -> [2, 2, 3, 4]

InChar

InChar - Input Character - awaits user input for a character and pushes it onto the stack.

InNum

InNum - Input Number - awaits user input for a number and pushes it onto the stack.

LoopBegin

LoopBegin signals the beginning of a loop.

LoopEnd

LoopEnd signals the end of a loop. Always loops back to the last LoopBegin.

Mult

Mult - Multiply - Multiplies the top two elements of the stack and pushes the result to the top of the stack.

E.g. [2, 3, 4] -> [6, 4]

NOP

NOP - No Operation - does nothing. Might be reserved for more functionality.

Over

Over pushes a opy of the second element of the stack onto the stack.

E.g. [2, 3, 4] -> [3, 2, 3, 4]

Pred

Pred - Predecessor - decrements the value of the top of the stack

Print

Print outputs all of the values in the stack until the NULL character: '\0'.

PrintNum

PrintNum - Print Number - prints the raw value of the top element of the stack.

Sub

Sub - Subtract - subtracts the top two numbers (first from the second) and pushes the result to the top of the stack.

E.g. [2, 3, 4] -> [1, 4

Succ

Succ - Successor - increments the value of the top of the stack]

Swap

Swap swaps the top two elements of the stack.

E.g. [2, 3, 4] -> [3, 2, 4]

Examples

The following program echoes back any number and exits when 0 is entered.

TODO

Implement track switching for sub-program functionality.
Better error handling.
Clean up codebase.
Add more examples.
Change note bindings based on frequency of use and interval.
Allow printing without newline
Change the stack to use numbers instead of characters.

ufosc/amuse