#Yo!Joy

Yo!Joy is a reversible programming language taking its primitives from Henry G. Baker's psi-lisp and Brent Kerby's concatenative combinators. It's not quite a htro-forth, but a stack machine made of cons cells or the reverse image of a linear lisp.

#Manual

#psi-lisp

Lossless.

• minus ( t -- -t ).
• not ( t -- ~t).
• xor ( n t -- n t^n )
• swp ( n t -- t n )
• inc ( n t -- n t+n ), inverse is dec.
• dec ( n t -- n t-n ), inverse is inc.
• csw ( l n t -- <n l> ?t ), if t=nil swap n and l.
• cons ( [n] t -- [n t] ), inverse is sonc.
• snoc ( [n t] -- [n] t ), inverse is cons.
• roll ( n t -- n t<<n ), leftward bit cycling, inverse is roll(t,-n).
• mul ( l n t -- l n l*n+t ), 0<=x<z, inverse is div.
• div ( l n t -- l n t-l*n ), 0<=x<z, inverse is mul.
• rot ( l n t -- n t l ), TODO.
• tor ( l n t -- t l n ), TODO.
• flip ( l n t -- t n l ), TODO.
• quote ( [t] -- '[t] ), TODO.
• eval ( [t] -- t ), TODO.
• apply ( n [t] -- t(n) ), TODO.

#concatenative combinators

Reversible but wastes allocation.

• i ( [t] -- t ), inverse is unit.
• unit ( t -- [t] ), inverse is i.

#non-linear(helpers)

Non-reversible.

• cdr ( n t -- n ), non reversible.

#Build

You must have an Uxn assembler and emulator.

uxnasm src/yo-joy.tal bin/yo-joy.rom
uxnemu bin/yo-joy.rom

If do not wish to assemble it yourself, you can download yo-joy.rom.

#Support

• theme
• snarf
• Assembled with drifblim
• Linted with uxnlin
• Formatted with uxnlin