Nuprl Lemma : w-isnull_wf
11,40
postcript
pdf
the_w
:World,
i
:Id,
a
:Action(
i
). isnull(
a
)
latex
Definitions
x
:
A
.
B
(
x
)
,
Action(
i
)
,
t
T
,
isnull(
a
)
,
w
.TA
,
w
.M
,
t
.1
,
t
.2
,
isl(
x
)
,
World
,
Action(
dec
)
Lemmas
action
wf
,
w-action-dec
wf
,
Id
wf
,
world
wf
,
btrue
wf
,
bfalse
wf
origin
the_w:World, i:Id, a:Action(i). isnull(a) 
the_w:World, i:Id, a:Action(i). isnull(a) x:A. B(x) T