ytaki0801

####
#### letLISP-REPL.py:
#### A Pure LISP Interpreter
#### with dynamic-scope named-let
#### in pseudocode-style Python 3
####
#### (C) 2022 TAKIZAWA Yozo
#### This code is licensed under CC0,
#### Creative Commons 0 as Public Domain
####

ytaki0801

# Wolfram's 2-state 3-symbol Turing Machine as an Universal TM
# with Turtle Graphics

from time import sleep
from turtle import fd, rt, lt, setpos, pu, pd

pu(); setpos(-300, 300); pd(); sleep(5)

delta = {1: {0: (1,  1, 2), 1: (2, -1, 1), 2: (1, -1, 1)},
         2: {0: (2, -1, 1), 1: (2,  1, 2), 2: (0,  1, 1)}}

ytaki0801

# Wolfram's 2-state 3-symbol Turing Machine

from time import sleep

delta = {1: {0: (1,  1, 2), 1: (2, -1, 1), 2: (1, -1, 1)},
         2: {0: (2, -1, 1), 1: (2,  1, 2), 2: (0,  1, 1)}}
ds = {0: ' ', 1: '.', 2: '*'}

tlen = 80
tape, head, state = [0] * tlen, int(tlen / 2) - 9, 1

ytaki0801

# Wolfram's 2-state 3-symbol Turing Machine as an Universal TM
# with Turtle Graphics

from time import sleep
from turtle import fd, rt, lt, setup, setpos, clear

setup(height=500); setpos(100, 0); clear(); sleep(5)

delta = {1: {0: (1,  1, 2), 1: (2, -1, 1), 2: (1, -1, 1)},
         2: {0: (2, -1, 1), 1: (2,  1, 2), 2: (0,  1, 1)}}

ytaki0801

import turtle, time

comm = {'fd': lambda n: turtle.fd(n),
        'rt': lambda n: turtle.rt(n),
        'lt': lambda n: turtle.lt(n)}

def logo(s, p, pe):
    while p < pe:
        if s[p] == 'loop':
            n = int(s[p + 1])

ytaki0801

# (2,3) Turing Machine as an UTM

from time import sleep

# (state,symbol) => (state,symbol,head)
delta = {(0,0): (1,1, 1),
         (0,1): (0,2,-1),
         (0,2): (0,1,-1),
         (1,0): (0,2,-1),
         (1,1): (1,2, 1),

ytaki0801

# (2,3) Turing Machine as an UTM

from time import sleep

# (state,symbol) => (state,symbol,head)
delta = {(0,0): (1,1, 1),
         (0,1): (0,2,-1),
         (0,2): (0,1,-1),
         (1,0): (0,2,-1),
         (1,1): (1,2, 1),

ytaki0801

from time import sleep

# (state,symbol) => (state,symbol,head)
delta = {(0,0):(1,1,+1), (0,1):(0,2,-1), (0,2):(0,1,-1),
         (1,0):(0,2,-1), (1,1):(1,2,+1), (1,2):(0,0,+1)}
ds = {0: ' ', 1: '.', 2: '*'}

tlen = 80
state, stack, stackT, head = 0, [0] * tlen, [], int(tlen / 2) - 10

ytaki0801

from time import sleep

# (state,symbol) => (state,symbol,head)
delta = {(0,0):(1,1,+1), (0,1):(0,2,-1), (0,2):(0,1,-1),
         (1,0):(0,2,-1), (1,1):(1,2,+1), (1,2):(0,0,+1)}
ds = {0: ' ', 1: '.', 2: '*'}

state, stackL, C, stackR = 0, [0]*29, 0, [0]*50

while len(stackL) > 0 and len(stackR) > 0:

ytaki0801

// Collatz Sequence on 2-tag system
// rule: {A -> BC, B -> A, C -> AAA}, value: AAA for 3, for example

// Translation from 2-tag system to cyclic tag system
const A = "100", B = "010", C = "001", S = " ";
const clist = [B+C, A, A+A+A, S, S, S];

function printn(q) {
    let n = 0;
    while (q.length != 0 && q.slice(0, 3) == A) {