Nuprl Lemma : test-lifting

x:Top. (if isl(x) then outl(x) else fi  case of inl(y) => inr(z) => 2)


Proof




Definitions occuring in Statement :  outl: outl(x) ifthenelse: if then else fi  isl: isl(x) top: Top all: x:A. B[x] decide: case of inl(x) => s[x] inr(y) => t[y] add: m natural_number: $n sqequal: t
Definitions unfolded in proof :  all: x:A. B[x] ifthenelse: if then else fi  isl: isl(x) uall: [x:A]. B[x] so_lambda: so_lambda(x,y,z,w.t[x; y; z; w]) member: t ∈ T so_apply: x[s1;s2;s3;s4] so_lambda: λ2x.t[x] top: Top so_apply: x[s] uimplies: supposing a btrue: tt outl: outl(x) strict4: strict4(F) and: P ∧ Q implies:  Q has-value: (a)↓ prop: or: P ∨ Q squash: T false: False bfalse: ff
Lemmas referenced :  lifting-strict-decide istype-void strict4-decide value-type-has-value int-value-type has-value_wf_base istype-base exception-not-value is-exception_wf strictness-add-right top_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity Error :lambdaFormation_alt,  sqequalRule cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin baseClosed Error :isect_memberEquality_alt,  voidElimination hypothesis independent_isectElimination independent_pairFormation callbyvalueAdd baseApply closedConclusion hypothesisEquality productElimination intEquality because_Cache Error :universeIsType,  addExceptionCases exceptionSqequal Error :inlFormation_alt,  imageMemberEquality imageElimination sqleReflexivity independent_functionElimination Error :inhabitedIsType,  sqequalSqle divergentSqle callbyvalueDecide unionElimination Error :equalityIsType1,  equalityTransitivity equalitySymmetry dependent_functionElimination decideExceptionCases axiomSqleEquality

Latex:
\mforall{}x:Top.  (if  isl(x)  then  1  +  outl(x)  else  2  fi    \msim{}  case  x  of  inl(y)  =>  1  +  y  |  inr(z)  =>  2)



Date html generated: 2019_06_20-PM-01_04_37
Last ObjectModification: 2019_06_20-PM-01_01_30

Theory : computation


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