Package list-length-def: Definition of the list length function
Information
name | list-length-def |
version | 1.30 |
description | Definition of the list length function |
author | Joe Hurd <joe@gilith.com> |
license | HOLLight |
provenance | HOL Light theory extracted on 2012-06-08 |
requires | bool list-def |
show | Data.Bool Data.List Number.Natural |
Files
- Package tarball list-length-def-1.30.tgz
- Theory file list-length-def.thy (included in the package tarball)
Defined Constant
- Data
- List
- length
- List
Theorems
⊦ length [] = 0
⊦ ∀h t. length (h :: t) = suc (length t)
Input Type Operators
- →
- bool
- Data
- List
- list
- List
- Number
- Natural
- natural
- Natural
Input Constants
- =
- select
- Data
- Bool
- ∀
- ∧
- ⇒
- ∃
- ⊤
- List
- ::
- []
- Bool
- Number
- Natural
- suc
- zero
- Natural
Assumptions
⊦ ⊤
⊦ (∃) = λp. p ((select) p)
⊦ (∀) = λp. p = λx. ⊤
⊦ (⇒) = λp q. p ∧ q ⇔ p
⊦ (∧) = λp q. (λf. f p q) = λf. f ⊤ ⊤
⊦ ∀p. (∀x. ∃y. p x y) ⇔ ∃y. ∀x. p x (y x)
⊦ ∀b f. ∃fn. fn [] = b ∧ ∀h t. fn (h :: t) = f h t (fn t)