diff options
| -rw-r--r-- | 064list.mu | 112 | ||||
| -rw-r--r-- | 066duplex_list.mu | 2 |
2 files changed, 113 insertions, 1 deletions
diff --git a/064list.mu b/064list.mu index 2106ad64..dd9a7f73 100644 --- a/064list.mu +++ b/064list.mu @@ -146,6 +146,118 @@ scenario inserting-after-start-of-list [ ] ] +# remove 'x' from its surrounding list 'in' +# +# Returns null if and only if list is empty. Beware: in that case any other +# pointers to the head are now invalid. +def remove x:address:list:_elem/contained-in:in, in:address:list:_elem -> in:address:list:_elem [ + local-scope + load-ingredients + # if 'x' is null, return + return-unless x + next-node:address:list:_elem <- rest x + # clear next pointer of 'x' + *x <- put *x, next:offset, 0 + # if 'x' is at the head of 'in', return the new head + at-head?:boolean <- equal x, in + return-if at-head?, next-node + # compute prev-node + prev-node:address:list:_elem <- copy in + curr:address:list:_elem <- rest prev-node + { + return-unless curr + found?:boolean <- equal curr, x + break-if found? + prev-node <- copy curr + curr <- rest curr + } + # set its next pointer to skip 'x' + *prev-node <- put *prev-node, next:offset, next-node +] + +scenario removing-from-list [ + run [ + local-scope + list:address:list:character <- push 3, 0 + list <- push 4, list + list <- push 5, list + list2:address:list:character <- rest list # second element + list <- remove list2, list + 10:boolean/raw <- equal list2, 0 + # check structure like before + list2 <- copy list + 11:character/raw <- first list2 + list2 <- rest list2 + 12:character/raw <- first list2 + 20:address:list:character/raw <- rest list2 + ] + memory-should-contain [ + 10 <- 0 # remove returned non-null + 11 <- 5 # scanning next, skipping deleted element + 12 <- 3 + 20 <- 0 # no more elements + ] +] + +scenario removing-from-start-of-list [ + run [ + local-scope + list:address:list:character <- push 3, 0 + list <- push 4, list + list <- push 5, list + list <- remove list, list + # check structure like before + list2:address:list:character <- copy list + 10:character/raw <- first list2 + list2 <- rest list2 + 11:character/raw <- first list2 + 20:address:list:character/raw <- rest list2 + ] + memory-should-contain [ + 10 <- 4 # scanning next, skipping deleted element + 11 <- 3 + 20 <- 0 # no more elements + ] +] + +scenario removing-from-end-of-list [ + run [ + local-scope + list:address:list:character <- push 3, 0 + list <- push 4, list + list <- push 5, list + # delete last element + list2:address:list:character <- rest list + list2 <- rest list2 + list <- remove list2, list + 10:boolean/raw <- equal list2, 0 + # check structure like before + list2 <- copy list + 11:character/raw <- first list2 + list2 <- rest list2 + 12:character/raw <- first list2 + 20:address:list:character/raw <- rest list2 + ] + memory-should-contain [ + 10 <- 0 # remove returned non-null + 11 <- 5 # scanning next, skipping deleted element + 12 <- 4 + 20 <- 0 # no more elements + ] +] + +scenario removing-from-singleton-list [ + run [ + local-scope + list:address:list:character <- push 3, 0 + list <- remove list, list + 1:number/raw <- copy list + ] + memory-should-contain [ + 1 <- 0 # back to an empty list + ] +] + def to-text in:address:list:_elem -> result:address:array:character [ local-scope load-ingredients diff --git a/066duplex_list.mu b/066duplex_list.mu index 183d2608..cefab1f8 100644 --- a/066duplex_list.mu +++ b/066duplex_list.mu @@ -325,7 +325,7 @@ scenario removing-from-end-of-duplex-list [ ] ] -scenario removing-from-singleton-list [ +scenario removing-from-singleton-duplex-list [ run [ local-scope list:address:duplex-list:character <- push 3, 0 |