Nuprl Lemma : oob-getleft_wf

[B,A:Type]. ∀[x:{x:one_or_both(A;B)| ↑oob-hasleft(x)} ].  (oob-getleft(x) ∈ A)


Proof




Definitions occuring in Statement :  oob-getleft: oob-getleft(x) oob-hasleft: oob-hasleft(x) one_or_both: one_or_both(A;B) assert: b uall: [x:A]. B[x] member: t ∈ T set: {x:A| B[x]}  universe: Type
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T oob-getleft: oob-getleft(x) all: x:A. B[x] implies:  Q bool: 𝔹 unit: Unit it: btrue: tt uiff: uiff(P;Q) and: P ∧ Q uimplies: supposing a ifthenelse: if then else fi  bfalse: ff subtype_rel: A ⊆B top: Top prop: so_lambda: λ2x.t[x] so_apply: x[s] oob-hasleft: oob-hasleft(x) or: P ∨ Q not: ¬A false: False
Lemmas referenced :  oobleft?_wf bool_wf eqtt_to_assert oobleft-lval_wf uiff_transitivity equal-wf-T-base assert_wf bnot_wf not_wf eqff_to_assert assert_of_bnot pi1_wf_top oobboth-bval_wf top_wf oob-subtype equal_wf set_wf one_or_both_wf oob-hasleft_wf assert_of_bor oobboth?_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut setElimination thin rename sqequalRule extract_by_obid sqequalHypSubstitution isectElimination cumulativity hypothesisEquality hypothesis lambdaFormation unionElimination equalityElimination because_Cache productElimination independent_isectElimination equalityTransitivity equalitySymmetry baseClosed independent_functionElimination applyEquality lambdaEquality isect_memberEquality voidElimination voidEquality dependent_functionElimination axiomEquality universeEquality

Latex:
\mforall{}[B,A:Type].  \mforall{}[x:\{x:one\_or\_both(A;B)|  \muparrow{}oob-hasleft(x)\}  ].    (oob-getleft(x)  \mmember{}  A)



Date html generated: 2018_05_21-PM-08_00_02
Last ObjectModification: 2017_07_26-PM-05_36_53

Theory : general


Home Index