l-x/fortheck
1
0
Fork 0
Code Issues Pull requests Releases Activity Actions

refactor: straighten stack - part III

Browse source
This commit is contained in:
Alex 2024-09-19 17:29:47 +02:00
parent f84d6fdc85
commit 4587bee699
Signed by: l-x
SSH key fingerprint: SHA256:MK3uQVPHEV0Oo2ry/dAqvVK3pAwegKAwSlyfgLd/yQM
1 changed files with 12 additions and 23 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

33
src/fortheck/stack.gleam
View file

@ -1,6 +1,5 @@
import gleam/bool import gleam/list.{reverse, try_fold}
import gleam/list import gleam/result.{then, try}
import gleam/result
pub type Error { pub type Error {
StackOverflow StackOverflow
@ -12,7 +11,7 @@ pub opaque type Stack(a) {
} }
pub fn new() -> Stack(a) { pub fn new() -> Stack(a) {
Stack(131_072, 0, []) Stack(capacity: 131_072, length: 0, data: [])
} }
pub fn from_list(list: List(a)) -> Result(Stack(a), Error) { pub fn from_list(list: List(a)) -> Result(Stack(a), Error) {
@ -20,23 +19,22 @@ pub fn from_list(list: List(a)) -> Result(Stack(a), Error) {
} }
pub fn to_list(stack: Stack(a)) -> List(a) { pub fn to_list(stack: Stack(a)) -> List(a) {
list.reverse(stack.data) reverse(stack.data)
} }
pub fn push(onto stack: Stack(a), this item: a) -> Result(Stack(a), Error) { pub fn push(onto stack: Stack(a), this item: a) -> Result(Stack(a), Error) {
use <- bool.guard( case stack.length < stack.capacity {
when: stack.length >= stack.capacity, True ->
return: Error(StackOverflow),
)
Ok(Stack(..stack, length: stack.length + 1, data: [item, ..stack.data])) Ok(Stack(..stack, length: stack.length + 1, data: [item, ..stack.data]))
False -> Error(StackOverflow)
}
} }
pub fn push_items( pub fn push_items(
onto stack: Stack(a), onto stack: Stack(a),
this items: List(a), this items: List(a),
) -> Result(Stack(a), Error) { ) -> Result(Stack(a), Error) {
list.try_fold(over: items, from: stack, with: push) try_fold(over: items, from: stack, with: push)
} }
pub fn pop(from stack: Stack(a)) -> Result(#(a, Stack(a)), Error) { pub fn pop(from stack: Stack(a)) -> Result(#(a, Stack(a)), Error) {
@ -47,17 +45,8 @@ pub fn pop(from stack: Stack(a)) -> Result(#(a, Stack(a)), Error) {
} }
pub fn pop_2(from stack: Stack(a)) -> Result(#(#(a, a), Stack(a)), Error) { pub fn pop_2(from stack: Stack(a)) -> Result(#(#(a, a), Stack(a)), Error) {
use #(b, stack) <- result.try(pop(from: stack)) use #(b, stack) <- try(pop(from: stack))
use #(a, stack) <- result.try(pop(from: stack)) use #(a, stack) <- then(pop(from: stack))
Ok(#(#(a, b), stack)) Ok(#(#(a, b), stack))
} }
pub fn try_pop_2(
from stack: Stack(a),
apply fun: fn(a, a, Stack(a)) -> Result(b, Error),
) -> Result(b, Error) {
use #(#(a, b), stack) <- result.try(pop_2(from: stack))
fun(a, b, stack)
}