| | Some definitions of interest. |
|
| assert | Def  b == if b True else False fi |
| | | Thm*  b: . b  Prop |
|
| swap | Def swap(L;i;j) == (L o (i, j)) |
| | | Thm* T:Type, L:T List, i,j: ||L||. swap(L;i;j) T List |
|
| flip | Def (i, j)(x) == if x= i j ; x=j i else x fi |
| | | Thm* k:, i,j:k. (i, j) k  k |
|
| int_seg | Def {i..j } == {k: | i  k < j } |
| | | Thm* m,n:. {m..n} Type |
|
| length | Def ||as|| == Case of as; nil 0 ; a.as' ||as'||+1 (recursive) |
| | | Thm* A:Type, l:A List. ||l|| |
| | | Thm* ||nil|| |
|
| not | Def  A == A   False |
| | | Thm* A:Prop. (A) Prop |
|
| select | Def l[i] == hd(nth_tl(i;l)) |
| | | Thm* A:Type, l:A List, n:. 0n n<||l|| l[n] A |
