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1
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2
:
3
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4
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5
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[
6
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7
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8
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9
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1
:
2
:
3
:
4
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5
:
6
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[
] +
+ [
7
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8
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9
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0
‚
[
1
,
2
,
3
,
4
,
5
,
6
,
7
,
8
,
9
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10
‚vvß—|¤ Ñﬁ ” Õç³÷̃öÀ|–o—¡

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Õç³Og ++
¡− ô7wvv−
(++)
»ìg ¶” Q©O•» t¶o ¡
g
h
c
i
> :
i (
+
+
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(
+
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: [
a
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> [
a
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> [
a
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f
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”øq¶Og ”™•¶›–|—q̃ Øm− |łq

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P) Õç³³uq
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e
w
t
y
p
e D
i
f
f
L
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t a = D
i
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t
D
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f
f
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a
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t
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D
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a
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t
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D
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f
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D
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D
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wwo ¡
t
o
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[
1
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4
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s
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[
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[
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(->) r, aka Reader

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9c»Žéè“›¤
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i
n
s
t
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e M
o
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a
d (
(
-
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r
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r
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b
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d
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n
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> I
n
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g
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h >
>
= f = \
w -
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»…̇
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>
=
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d
d
O
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r
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w -
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State

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1\
n
e
w
t
y
p
e S
t
a
t
e s a = S
t
a
t
e { r
u
n
S
t
a
t
e :
: s -
> (
a
, s
) }
i
n
s
t
a
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c
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o
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a
d (
S
t
a
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r
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t
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S
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t
a
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a
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w
S
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S
t
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ÕÜáË³State
Žéè
-
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m
p
o
r
t C
o
n
t
r
o
l
.
M
o
n
a
d
.
S
t
a
t
e
t
y
p
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t
a
c
k = [
I
n
t
]
p
o
p :
: S
t
a
t
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t
a
c
k I
n
t
p
o
p = s
t
a
t
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(
x
:
x
s
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> (
x
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s
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p
u
s
h :
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n
t -
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t
a
t
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t
a
c
k (
)
p
u
s
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t
a
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(
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:
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t
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t
a
t
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t
a
c
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)
s
t
a
c
k
S
t
u
f
f = d
o
a <
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= 5
t
h
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p
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h
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t
a
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t
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f [
9
,
0
,
2
,
1
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]
(
(
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[
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,
3
,
0
,
2
,
1
,
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]
)

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ƒc¢{P³State
Žéè
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t
h
r
e
e
C
o
i
n
s :
: S
t
d
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e
n -
> (
B
o
o
l
, B
o
o
l
, B
o
o
l
)
t
h
r
e
e
C
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i
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s g
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l
e
t (
f
i
r
s
t
C
o
i
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w
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a
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d
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m g
e
n
(
s
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c
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d
C
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w
G
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n
'
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a
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d
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m n
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w
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(
t
h
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C
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a
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f
i
r
s
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o
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c
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h
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C
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a
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d
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S
t :
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R
a
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d
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G
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, R
a
n
d
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t
a
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r
a
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d
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m
S
t = s
t
a
t
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a
n
d
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m
t
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r
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e
C
o
i
n
s :
: S
t
a
t
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t
d
G
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n (
B
o
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l
, B
o
o
l
, B
o
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l
)
t
h
r
e
e
C
o
i
n
s = d
o
a <
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a
n
d
o
m
S
t
b <
- r
a
n
d
o
m
S
t
c <
- r
a
n
d
o
m
S
t
r
e
t
u
r
n (
a
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g
h
c
i
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u
n
S
t
a
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h
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e
C
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s (
m
k
S
t
d
G
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n 3
3
)
(
(
T
r
u
e
,
F
a
l
s
e
,
T
r
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)
,
6
8
0
0
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1
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3
4
1
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6
3
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Error
³F•
1\
i
n
s
t
a
n
c
e (
E
r
r
o
r e
) =
> M
o
n
a
d (
E
i
t
h
e
r e
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h
e
r
e
r
e
t
u
r
n x = R
i
g
h
t x
R
i
g
h
t x >
>
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L
e
f
t e
r
r >
>
= f = L
e
f
t e
r
r
f
a
i
l m
s
g = L
e
f
t (
s
t
r
M
s
g m
s
g
)
Nothing
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s© øo |łq
g
h
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f
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b
o
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x -
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r
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x
+
1
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L
e
f
t "
b
o
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m
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g
h
c
i
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i
g
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t 1
0
0 >
>
= \
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e
f
t "
n
o w
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L
e
f
t "
n
o w
a
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g
h
c
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i
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h
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t
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0
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<
i
n
t
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r
a
c
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1
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A
m
b
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o
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s t
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p
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a
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a
b
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a
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t
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E
r
r
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r
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3
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a
b
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d
d a t
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p
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a
t
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h
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t f
i
x
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s t
h
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s
e t
y
p
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a
r
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a
b
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(
s
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g
h
c
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i
t
h
e
r e a
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h
c
i
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i
g
h
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e
t
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r
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x + 1
0
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i
t
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e
r S
t
r
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R
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3

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Žéå½áË9c

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liftM
l
i
f
t
M :
: (
M
o
n
a
d m
) =
> (
a -
> b
) -
> m a -
> m b
l
i
f
t
M f m = d
o
x <
- m
r
e
t
u
r
n (
f x
)
fmap
œ∼ ¡
g
h
c
i
> l
i
f
t
M (
*
3
) (
J
u
s
t 8
)
J
u
s
t 2
4
g
h
c
i
> f
m
a
p (
*
3
) (
J
u
s
t 8
)
J
u
s
t 2
4
g
h
c
i
> r
u
n
W
r
i
t
e
r $ l
i
f
t
M n
o
t $ W
r
i
t
e
r (
T
r
u
e
, "
c
h
i
c
k
p
e
a
s
"
)
(
F
a
l
s
e
, "
c
h
i
c
k
p
e
a
s
"
)
g
h
c
i
> r
u
n
W
r
i
t
e
r $ f
m
a
p n
o
t $ W
r
i
t
e
r (
T
r
u
e
, "
c
h
i
c
k
p
e
a
s
"
)
(
F
a
l
s
e
, "
c
h
i
c
k
p
e
a
s
"
)
g
h
c
i
> r
u
n
S
t
a
t
e (
l
i
f
t
M (
+
1
0
0
) p
o
p
) [
1
, 2
, 3
, 4
]
(
1
0
1
, [
2
, 3
, 4
]
)
g
h
c
i
> r
u
n
S
t
a
t
e (
f
m
a
p (
+
1
0
0
) p
o
p
) [
1
, 2
, 3
, 4
]
(
1
0
1
, [
2
, 3
, 4
]
)
é¼O¶LÂ Monad
»Functor
»¶o” liftM
wi²\©–o−øq
¡

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ap
a
p :
: (
M
o
n
a
d m
) =
> m (
a -
> b
) -
> m a -
> m b
a
p m
f m = d
o
f <
- m
f
x <
- m
r
e
t
u
r
n (
f x
)
<
*
>
œ∼ ¡
g
h
c
i
> J
u
s
t (
+
3
) <
*
> J
u
s
t 4
J
u
s
t 7
g
h
c
i
> J
u
s
t (
+
3
) `
a
p
` J
u
s
t 4
J
u
s
t 7
g
h
c
i
> [
(
+
1
)
, (
+
2
)
, (
+
3
)
] <
*
> [
1
0
, 1
1
]
[
1
1
, 1
2
, 1
2
, 1
3
, 1
3
, 1
4
]
g
h
c
i
> [
(
+
1
)
, (
+
2
)
, (
+
3
)
] `
a
p
` [
1
0
, 1
1
]
[
1
1
, 1
2
, 1
2
, 1
3
, 1
3
, 1
4
]
é¼O¶LÂ Monad
»Applicative
»¶o” liftM
wi²\©–o−ø
q ¡

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join
ìÕç|¤Žéè³— Ł–z©—¡
j
o
i
n :
: (
M
o
n
a
d m
) =
> m (
m a
) -
> m a
j
o
i
n m
m = d
o
m <
- m
m
m
g
h
c
i
> j
o
i
n (
J
u
s
t (
J
u
s
t 9
)
)
J
u
s
t 9
g
h
c
i
> j
o
i
n (
J
u
s
t N
o
t
h
i
n
g
)
N
o
t
h
i
n
g
g
h
c
i
> j
o
i
n N
o
t
h
i
n
g
N
o
t
h
i
n
g
g
h
c
i
> j
o
i
n [
[
1
, 2
, 3
]
, [
4
, 5
, 6
]
]
[
1
, 2
, 3
, 4
, 5
, 6
]
g
h
c
i
> r
u
n
W
r
i
t
e
r $ j
o
i
n (
W
r
i
t
e
r (
W
r
i
t
e
r (
1
, "
a
a
a
"
)
, "
b
b
b
"
)
)
(
1
, "
b
b
b
a
a
a
"
)
À
́³— Ł−”•øz³o—¡Á

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filterM, foldM
’ (” ß ¡

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もうちょっとだけモナド

もうちょっとだけモナド

Fujimura Daisuke

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