Nuprl Lemma : alpha-rename-alist-nonnullvar

[opr:Type]
  ∀t:term(opr). ∀L:varname() List. ∀x,x':varname().
    ((<x, x'> ∈ alpha-rename-alist(t;L))  (x' nullvar() ∈ varname())  (nullvar() ∈ L))


Proof




Definitions occuring in Statement :  alpha-rename-alist: alpha-rename-alist(t;L) term: term(opr) nullvar: nullvar() varname: varname() l_member: (x ∈ l) list: List uall: [x:A]. B[x] all: x:A. B[x] implies:  Q pair: <a, b> product: x:A × B[x] universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] alpha-rename-alist: alpha-rename-alist(t;L) member: t ∈ T so_lambda: λ2y.t[x; y] has-value: (a)↓ uimplies: supposing a varname: varname() so_lambda: λ2x.t[x] so_apply: x[s] so_apply: x[s1;s2] guard: {T} prop: implies:  Q pi2: snd(t) and: P ∧ Q nil: [] it: not: ¬A false: False iff: ⇐⇒ Q or: P ∨ Q pi1: fst(t) squash: T true: True subtype_rel: A ⊆B rev_implies:  Q
Lemmas referenced :  list_accum_invariant2 varname_wf list_wf value-type-has-value bunion-value-type nat_wf atom-value-type product-value-type istype-atom maybe_new_var_wf cons_wf l_member_wf pi2_wf equal-wf-T-base nullvar_wf append_wf all-vars_wf nil_wf null_nil_lemma btrue_wf null_wf member-implies-null-eq-bfalse btrue_neq_bfalse cons_member pi1_wf term_wf istype-universe maybe_new_var-is-null squash_wf true_wf subtype_rel_self iff_weakening_equal
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt lambdaFormation_alt cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin hypothesis productEquality dependent_functionElimination sqequalRule lambdaEquality_alt productElimination callbyvalueReduce independent_isectElimination atomEquality because_Cache hypothesisEquality independent_pairEquality closedConclusion universeIsType productIsType functionEquality inhabitedIsType baseClosed independent_functionElimination voidEquality equalitySymmetry dependent_set_memberEquality_alt independent_pairFormation equalityTransitivity equalityIstype applyLambdaEquality setElimination rename voidElimination unionElimination functionIsType instantiate universeEquality applyEquality imageElimination natural_numberEquality imageMemberEquality

Latex:
\mforall{}[opr:Type]
    \mforall{}t:term(opr).  \mforall{}L:varname()  List.  \mforall{}x,x':varname().
        ((<x,  x'>  \mmember{}  alpha-rename-alist(t;L))  {}\mRightarrow{}  (x'  =  nullvar())  {}\mRightarrow{}  (nullvar()  \mmember{}  L))



Date html generated: 2020_05_19-PM-09_57_15
Last ObjectModification: 2020_03_09-PM-04_09_37

Theory : terms


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