User:MarkFan8901/Sandbox

FAI

FAI (short for Forth Artificial Intelligence) is a concatenative esolang made by User:MarkFan8901 which is intended to be used in wikipedia:linear genetic programming. The core of the language is inspired by the thought of how functions could be made to work in a GP context, and the idea of 'accidental' control flow (that is, operators which can still 'meaningfully' control the flow of a program, even in a completely random context).

Syntax

Words and numbers are separated by whitespace, as per usual. However, newlines aren't whitespace; they delimit functions, such that each line of a program is a function. Function calls (referred to as 'line calls') are written with a $ followed by the line number being called (starting from 1), for example $4. Comments are written within parentheses.

Words

Stack words

Word	Signature	Meaning
pop	(a -- )	Pops the top value.
dup	(a -- a a)	Duplicates the top value.
over	(a b -- a b a)	Duplicates the second-top value.
swap	(a b -- b a)	Swaps the two top values.
rot	(a b c -- b c a)	Rotates the top three values.
2pop	(a₂ -- )	Pops the top two values.
2dup	(a₂ -- a₂ a₂)	Duplicates the top two values.
...	...	Etc. for the other stack words.

Arithmetic words

Word	Signature	Meaning
+	(a b -- a+b)	Pushes the sum of a and b.
-	(a b -- a-b)	Pushes the difference of a and b.
*	(a b -- a*b)	Pushes the product of a and b.
/	(a b -- a/b)	Pushes the quotient of a and b.
%	(a b -- a%b)	Pushes the remainder of a and b.
±	(a -- sign(a))	Pushes 1 if a is positive, 0 if a is 0, and -1 if a is negative.

Comparison words

Word	Signature	Meaning
<	(a b -- a<b)	Pushes 1 if a is less than b, and 0 otherwise.
=	(a b -- a=b)	Pushes 1 if a is equal to b, and 0 otherwise.
>	(a b -- a>b)	Pushes 1 if a is greater than b, and 0 otherwise.
!<	(a b -- a!<b)	Pushes 0 if a is less than b, and 1 otherwise.
!=	(a b -- a!=b)	Pushes 0 if a is equal to b, and 1 otherwise.
!>	(a b -- a!>b)	Pushes 0 if a is greater than b, and 1 otherwise.
!	(a -- !a)	Pushes 1 if a is 0, and 0 otherwise.

Special words

Word	Signature	Meaning
empty	( -- a)	Pushes an empty (see below).
sleep	(a -- a?)	If a is 0, pop it and ignore the next line call/sleep.

Semantics

Programs are executed by calling their last line.

The stack is initialized with an infinite number of empties. Empties are the lack of a value, and work as identity values in arithmetic (for example, anything times an empty is itself). Comparing anything with an empty also results in itself. ± and ! don't do anything to empties, however drop, dup, etc. do.

bla bla we'll finish this later

here have a truth machine as a treat

dup $1 (no i/o so dup is used for output instead)
sleep $1 0
0 $2 (replace 0 with your input)

weird fungelike

Command	Meaning
0-9	multiply the top of the stack by 10 and add 0-9
/	divide by 9
\	divide by 11