Nuprl Lemma : p-conditional_wf
11,40
postcript
pdf
A
,
B
:Type,
f
,
g
:(
A
(
B
+ Top)). [
f
?
g
]
A
(
B
+ Top)
latex
ProofTree
Definitions
Type
,
t
T
,
Top
,
left
+
right
,
x
:
A
B
(
x
)
,
Void
,
x
:
A
.
B
(
x
)
,
x
:
A
.
B
(
x
)
,
S
T
,
f
(
a
)
,
suptype(
S
;
T
)
,
can-apply(
f
;
x
)
,
if
b
then
t
else
f
fi
,
x
.
A
(
x
)
,
[
f
?
g
]
Lemmas
ifthenelse
wf
,
can-apply
wf
,
top
wf
origin
A, B:Type, f, g:(A
(B + Top)). [f?g] 
A(B + Top)
A, B:Type, f, g:(A(B + Top)). [f?g] A(B + Top)
TB(x)
x:A.B(x)x:A. B(x)
T
x.A(x)