name | list-take-drop-def |
version | 1.14 |
description | list-take-drop-def |
author | Joe Hurd <joe@gilith.com> |
license | HOLLight |
provenance | HOL Light theory extracted on 2011-07-25 |
show | Data.Bool |
⊦ (∀l. Data.List.drop 0 l = l) ∧
∀n h t.
Number.Natural.≤ n (Data.List.length t) ⇒
Data.List.drop (Number.Natural.suc n) (Data.List.:: h t) =
Data.List.drop n t
⊦ (∀l. Data.List.take 0 l = Data.List.[]) ∧
∀n h t.
Number.Natural.≤ n (Data.List.length t) ⇒
Data.List.take (Number.Natural.suc n) (Data.List.:: h t) =
Data.List.:: h (Data.List.take n t)
⊦ T
⊦ (∃) = λP. P ((select) P)
⊦ ∀t. (∀x. t) ⇔ t
⊦ (∀) = λp. p = λx. T
⊦ ∀x. x = x ⇔ T
⊦ (⇒) = λp q. p ∧ q ⇔ p
⊦ ∀h t. Data.List.head (Data.List.:: h t) = h
⊦ ∀h t. Data.List.tail (Data.List.:: h t) = t
⊦ (∧) = λp q. (λf. f p q) = λf. f T T
⊦ (∃) = λP. ∀q. (∀x. P x ⇒ q) ⇒ q
⊦ ∀e f. ∃fn. fn 0 = e ∧ ∀n. fn (Number.Natural.suc n) = f (fn n) n
⊦ ∀t. (T ∧ t ⇔ t) ∧ (t ∧ T ⇔ t) ∧ (F ∧ t ⇔ F) ∧ (t ∧ F ⇔ F) ∧ (t ∧ t ⇔ t)
⊦ ∀t. (T ⇒ t ⇔ t) ∧ (t ⇒ T ⇔ T) ∧ (F ⇒ t ⇔ T) ∧ (t ⇒ t ⇔ T) ∧ (t ⇒ F ⇔ ¬t)