refactor: straighten stack

This commit is contained in:
Alex 2024-09-19 16:37:07 +02:00
parent 1e6773ac28
commit 2b83aea200
Signed by: l-x
SSH key fingerprint: SHA256:MK3uQVPHEV0Oo2ry/dAqvVK3pAwegKAwSlyfgLd/yQM
2 changed files with 10 additions and 26 deletions

View file

@ -12,7 +12,7 @@ pub fn new() -> Stack(a) {
}
pub fn from_list(list: List(a)) -> Result(Stack(a), Error) {
list.try_fold(over: list, from: new(), with: push)
push_items(onto: new(), this: list)
}
pub fn to_list(stack: Stack(a)) -> List(a) {
@ -28,6 +28,13 @@ pub fn push(onto stack: Stack(a), this item: a) -> Result(Stack(a), Error) {
Ok(Stack(..stack, length: stack.length + 1, data: [item, ..stack.data]))
}
pub fn push_items(
onto stack: Stack(a),
this items: List(a),
) -> Result(Stack(a), Error) {
list.try_fold(over: items, from: stack, with: push)
}
pub fn pop(from stack: Stack(a)) -> Result(#(a, Stack(a)), Error) {
case stack.data {
[] -> Error(StackUnderflow)
@ -35,18 +42,9 @@ pub fn pop(from stack: Stack(a)) -> Result(#(a, Stack(a)), Error) {
}
}
pub fn try_pop(
from stack: Stack(a),
apply fun: fn(a, Stack(a)) -> Result(b, Error),
) -> Result(b, Error) {
use #(item, stack) <- result.try(pop(from: stack))
fun(item, stack)
}
pub fn pop_2(from stack: Stack(a)) -> Result(#(#(a, a), Stack(a)), Error) {
use b, stack <- try_pop(from: stack)
use a, stack <- try_pop(from: stack)
use #(b, stack) <- result.try(pop(from: stack))
use #(a, stack) <- result.try(pop(from: stack))
Ok(#(#(a, b), stack))
}

View file

@ -58,13 +58,6 @@ pub fn pop_test() {
|> should.be_ok
|> pair.first
|> should.equal(3)
{
use a, _ <- stack.try_pop(stack)
Ok(a)
}
|> should.be_ok
|> should.equal(3)
}
pub fn pop_2_test() {
@ -75,13 +68,6 @@ pub fn pop_2_test() {
|> should.be_ok
|> pair.first
|> should.equal(#(2, 3))
{
use a, b, _ <- stack.try_pop_2(stack)
Ok(#(a, b))
}
|> should.be_ok
|> should.equal(#(2, 3))
}
pub fn pop_2_stack_underflow_test() {