-
Notifications
You must be signed in to change notification settings - Fork 0
/
turing.py
184 lines (141 loc) · 5.03 KB
/
turing.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
from simulator import StateMachine, MachineControl
class TuringMachine(StateMachine):
def __init__(self, ctl, ctx, table, init_state, default=None,
show_steps=True):
super().__init__(ctl, ctx)
self.table = table
self.state = init_state
self.default = default
self.show_steps = show_steps
self.tape = None
self.action = None
self.write = None
self.next_state = None
self.init_state = self.setup
def __repr__(self):
return '<TM: %s>' % (self.current_state.__name__)
def setup(self):
self.tape = self.start_machine(TuringTape, self.default,
self.show_steps)
self.when_machine_emits('read', self.tape, self.step)
def step(self):
if self.show_steps:
print('State: %s, read: %s' % (self.state, self.event.value))
try:
self.action, self.write, self.next_state = (
self.table[self.state][self.event.value])
except KeyError:
print('Don\'t know what to do, halting!')
return self.halt
if self.show_steps:
print('Action: %s, write: %s, next state: %s' % (
self.action, self.write, self.next_state))
self.emit_to(self.tape, self.action, value=self.write)
if self.next_state == 'halt':
return self.halt
self.state = self.next_state
class TuringTape(StateMachine):
def __init__(self, ctl, ctx, default, show_steps, dsp_width=5):
super().__init__(ctl, ctx)
self.default = default
self.show_steps = show_steps
self.dsp_w = dsp_width
self.tape = [default]*(2 * dsp_width + 1)
self.i = dsp_width
self.init_state = self.setup
def __repr__(self):
return '<TT: %s>' % (self.current_state.__name__)
def setup(self):
self.when('L', self.action)
self.when('R', self.action)
self.when('N', self.action)
self.when('halt', self.dump)
return self.read
def read(self):
if self.show_steps:
print('Tape',
self.tape[(self.i - self.dsp_w):(self.i + self.dsp_w + 1)])
self.emit_to(self.ctx, 'read', value=self.tape[self.i])
def action(self):
self.tape[self.i] = self.event.value
if self.event.typ == 'L':
return self.move_left
if self.event.typ == 'R':
return self.move_right
if self.event.typ == 'N':
return self.read
if self.event.typ == 'halt':
return self.listen
# TODO: emit crash to ctx.
print('Unkown action, halting!')
return self.halt
def move_left(self):
self.i -= 1
if self.i < self.dsp_w:
self.tape = [self.default] + self.tape
self.i += 1
return self.read
def move_right(self):
self.i += 1
if (self.i + self.dsp_w) == len(self.tape):
self.tape.append(self.default)
return self.read
def dump(self):
print('Full tape')
print(self.tape)
return self.halt
if __name__ == '__main__':
ctl = MachineControl()
# Test.
# ctl.run(TuringMachine, {
# 'A': {None: ('R', '1', 'B'),
# '1': ('R', '0', 'B'), },
# 'B': {None: ('L', '1', 'A'),
# '1': ('N', '1', 'halt'), },
# }, 'A')
# Busy beaver 1.
# ctl.run(TuringMachine, {
# 'A': {'0': ('R', '1', 'B'),
# '1': ('L', '1', 'B')},
# 'B': {'0': ('L', '1', 'A'),
# '1': ('L', '0', 'C')},
# 'C': {'0': ('R', '1', 'halt'),
# '1': ('L', '1', 'D')},
# 'D': {'0': ('R', '1', 'D'),
# '1': ('R', '0', 'A')},
# }, 'A', default='0')
# Busy beaver 2.
# ctl.run(TuringMachine, {
# 'A': {'0': ('R', '1', 'B'),
# '1': ('L', '1', 'B')},
# 'B': {'0': ('L', '1', 'A'),
# '1': ('R', '1', 'halt')},
# }, 'A', default='0')
# Busy beaver 3. This one is insane.
# ctl.run(TuringMachine, {
# 'A': {'0': ('R', '1', 'B'),
# '1': ('L', '1', 'E')},
# 'B': {'0': ('R', '1', 'C'),
# '1': ('R', '1', 'F')},
# 'C': {'0': ('L', '1', 'D'),
# '1': ('R', '0', 'B')},
# 'D': {'0': ('R', '1', 'E'),
# '1': ('L', '0', 'C')},
# 'E': {'0': ('L', '1', 'A'),
# '1': ('R', '0', 'D')},
# 'F': {'0': ('L', '1', 'halt'),
# '1': ('R', '1', 'C')},
# }, 'A', default='0', show_steps=False)
# Busy beaver 4.
ctl.run(TuringMachine, {
'A': {'0': ('R', '1', 'B'),
'1': ('L', '1', 'C')},
'B': {'0': ('R', '1', 'C'),
'1': ('R', '1', 'B')},
'C': {'0': ('R', '1', 'D'),
'1': ('L', '0', 'E')},
'D': {'0': ('L', '1', 'A'),
'1': ('L', '1', 'D')},
'E': {'0': ('R', '1', 'halt'),
'1': ('L', '0', 'A')},
}, 'A', default='0', show_steps=False)