Skip to content

Implement min_by, min_by_key, max_by, and max_by_key #20

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open

Implement min_by, min_by_key, max_by, and max_by_key #20

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
62 changes: 61 additions & 1 deletion glsp-stdlib/src/num.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,4 +1,4 @@
use glsp::{bail, ensure, GResult, Num, rfn, Val};
use glsp::{bail, ensure, GResult, GFn, Root, Num, rfn, Val};
use smallvec::SmallVec;
use std::cmp::Ordering;
use std::f32;
Expand Down Expand Up @@ -29,7 +29,11 @@ pub fn init(_sandboxed: bool) -> GResult<()> {
glsp::bind_rfn(">=", rfn!(gte))?;
glsp::bind_rfn("ord", rfn!(ord))?;
glsp::bind_rfn("min", rfn!(min))?;
glsp::bind_rfn("min-by", rfn!(min_by))?;
glsp::bind_rfn("min-by-key", rfn!(min_by_key))?;
glsp::bind_rfn("max", rfn!(max))?;
glsp::bind_rfn("max-by", rfn!(max_by))?;
glsp::bind_rfn("max-by-key", rfn!(max_by_key))?;
glsp::bind_rfn("clamp", rfn!(clamp))?;

glsp::bind_rfn("round", rfn!(round))?;
Expand Down Expand Up @@ -140,6 +144,18 @@ fn sign(num: Num) -> i32 {
}
}

// Used to implement min_by and min_by_key
fn min_of<T, R, F: FnOnce(T, T) -> GResult<Ordering>>(
(t0, b0): (R, T),
(t1, b1): (R, T),
compare: F,
) -> GResult<R> {
Ok(match compare(b0, b1)? {
Ordering::Less | Ordering::Equal => t0,
Ordering::Greater => t1,
})
}

fn min(first: Val, rest: &[Val]) -> GResult<Val> {
ensure!(rest.iter().all(|val| val.is_int() || val.is_flo() || val.is_char()),
"non-number passed to min");
Expand All @@ -148,6 +164,34 @@ fn min(first: Val, rest: &[Val]) -> GResult<Val> {
}))
}

fn min_by(ord_f: Root<GFn>, first: Val, rest: &[Val]) -> GResult<Val> {
rest.iter().try_fold(&first, |accum, arg| {
min_of((accum, accum), (arg, arg), |v1, v2| glsp::call(&ord_f, &(v1, v2)))
}).map(|x| x.clone())
}

fn min_by_key(map_f: Root<GFn>, first: Val, rest: &[Val]) -> GResult<Val> {
rest.iter().try_fold(&first, |accum, arg| {
min_of(
(accum, glsp::call(&map_f, &[accum])?),
(arg, glsp::call(&map_f, &[arg])?),
ord,
)
}).map(|x| x.clone())
}

// Used to implement max_by and max_by_key
fn max_of<T, R, F: FnOnce(T, T) -> GResult<Ordering>>(
(t0, b0): (R, T),
(t1, b1): (R, T),
compare: F,
) -> GResult<R> {
Ok(match compare(b0, b1)? {
Ordering::Greater | Ordering::Equal => t0,
Ordering::Less => t1,
})
}

fn max(first: Val, rest: &[Val]) -> GResult<Val> {
ensure!(rest.iter().all(|val| val.is_int() || val.is_flo() || val.is_char()),
"non-number passed to max");
Expand All @@ -156,6 +200,22 @@ fn max(first: Val, rest: &[Val]) -> GResult<Val> {
}))
}

fn max_by(ord_f: Root<GFn>, first: Val, rest: &[Val]) -> GResult<Val> {
rest.iter().try_fold(&first, |accum, arg| {
max_of((accum, accum), (arg, arg), |v1, v2| glsp::call(&ord_f, &(v1, v2)))
}).map(|x| x.clone())
}

fn max_by_key(map_f: Root<GFn>, first: Val, rest: &[Val]) -> GResult<Val> {
rest.iter().try_fold(&first, |accum, arg| {
max_of(
(accum, glsp::call(&map_f, &[accum])?),
(arg, glsp::call(&map_f, &[arg])?),
ord,
)
}).map(|x| x.clone())
}

fn clamp(n: Val, min: Val, max: Val) -> GResult<Val> {
for val in &[&n, &min, &max] {
ensure!(val.is_int() || val.is_flo() || val.is_char(), "non-number passed to clamp");
Expand Down