Nuprl Lemma : bag-member-map3

[T,U:Type].  ∀x:U. ∀bs:bag(T). ∀f:{v:T| v ↓∈ bs}  ⟶ U.  uiff(x ↓∈ bag-map(f;bs);↓∃v:T. (v ↓∈ bs ∧ (x (f v) ∈ U)))


Proof




Definitions occuring in Statement :  bag-member: x ↓∈ bs bag-map: bag-map(f;bs) bag: bag(T) uiff: uiff(P;Q) uall: [x:A]. B[x] all: x:A. B[x] exists: x:A. B[x] squash: T and: P ∧ Q set: {x:A| B[x]}  apply: a function: x:A ⟶ B[x] universe: Type equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] all: x:A. B[x] member: t ∈ T prop: uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a squash: T exists: x:A. B[x] cand: c∧ B so_lambda: λ2x.t[x] so_apply: x[s] iff: ⇐⇒ Q rev_implies:  Q implies:  Q bag-member: x ↓∈ bs
Lemmas referenced :  bag-member_wf bag-map-member-wf bag-member-map bag-subtype equal_wf squash_wf exists_wf bag-subtype2 iff_weakening_uiff bag_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt lambdaFormation_alt cut introduction extract_by_obid sqequalHypSubstitution isectElimination thin hypothesisEquality because_Cache hypothesis setEquality dependent_functionElimination equalityTransitivity equalitySymmetry independent_pairFormation imageElimination productElimination setElimination rename dependent_pairFormation productEquality applyEquality dependent_set_memberEquality sqequalRule imageMemberEquality baseClosed universeIsType lambdaEquality independent_functionElimination independent_isectElimination functionIsType setIsType inhabitedIsType universeEquality

Latex:
\mforall{}[T,U:Type].
    \mforall{}x:U.  \mforall{}bs:bag(T).  \mforall{}f:\{v:T|  v  \mdownarrow{}\mmember{}  bs\}    {}\mrightarrow{}  U.    uiff(x  \mdownarrow{}\mmember{}  bag-map(f;bs);\mdownarrow{}\mexists{}v:T.  (v  \mdownarrow{}\mmember{}  bs  \mwedge{}  (x  =  (f  v)))\000C)



Date html generated: 2019_10_15-AM-11_02_23
Last ObjectModification: 2018_09_27-AM-11_19_30

Theory : bags


Home Index