Files
orchid/orchid-std/src/macros/stdlib/tuple.rs

122 lines
3.9 KiB
Rust

use async_fn_stream::stream;
use futures::{StreamExt, stream};
use orchid_base::{OrcRes, sym};
use orchid_extension::gen_expr::{GExpr, call, new_atom};
use orchid_extension::tree::{GenMember, fun, prefix};
use orchid_extension::{Expr, TAtom, ToExpr, exec};
use crate::macros::match_macros::{MatcherAtom, match_one};
use crate::macros::utils::{RuleCtx, build_macro, mactree, mactreev};
use crate::{HomoTpl, MacTree, OrcOpt};
pub async fn gen_tuple_macro_lib() -> Vec<GenMember> {
prefix("std::tuple", [
build_macro(None, ["t"])
.rule(mactreev!("std::tuple::t" [ "...$" elements 0 ]), async |mut cx, [elements]| {
let tup: HomoTpl<TAtom<MacTree>> =
cx.recur_call(mactree!("macros::common::comma_list" "push" elements)).await?;
let val = stream(async |mut h| {
for item in &tup.0[..] {
h.emit(cx.recur(item.own().await).await).await
}
})
.fold(mactree!("std::tuple::empty"), async |head, new| {
mactree!(
"std::tuple::cat"
"push" head;
("std::tuple::one"
"push" new)
)
})
.await;
Ok(val)
})
.rule(
mactreev!("pattern::match_rule"(
"std::tuple::t"[ "...$" elements 0 "macros::common::," "macros::common::.."]
)),
async |cx, [elements]| parse_tpl(cx, elements, Some(mactree!("macros::common::_"))).await,
)
.rule(
mactreev!("pattern::match_rule"(
"std::tuple::t"[ "...$" elements 1 "macros::common::," "macros::common::.." "...$" tail 0]
)),
async |cx, [elements, tail]| parse_tpl(cx, elements, Some(tail)).await,
)
.rule(
mactreev!("pattern::match_rule"("std::tuple::t"[ "...$" elements 0])),
async |cx, [elements]| parse_tpl(cx, elements, None).await,
)
.finish(),
fun(false, "matcher_body", tuple_matcher_body),
])
}
async fn parse_tpl(
mut cx: RuleCtx<'_>,
elements: MacTree,
tail_matcher: Option<MacTree>,
) -> OrcRes<MacTree> {
let tup: HomoTpl<TAtom<MacTree>> =
cx.recur_call(mactree!("macros::common::comma_list" "push" elements)).await?;
let mut keys = Vec::new();
let mut sub_matchers = mactree!("std::tuple::empty");
for mac_a in &tup.0[..] {
let sub: TAtom<MatcherAtom> =
cx.recur_call(mactree!("pattern::match_rule" ("push" mac_a.own().await))).await?;
let owned = sub.own().await;
keys.extend(owned.keys);
sub_matchers =
mactree!("std::tuple::cat" "push" sub_matchers; ("std::tuple::one" "push" owned.matcher));
}
let tail_matcher = match tail_matcher {
Some(mac) => {
let atm: TAtom<MatcherAtom> =
cx.recur_call(mactree!("pattern::match_rule" "push" mac)).await?;
let owned = atm.own().await;
keys.extend(owned.keys);
mactree!("std::option::some" "push" owned.matcher)
},
None => mactree!("std::option::none"),
};
Ok(mactree!("Val" new_atom(MatcherAtom {
keys,
matcher: mactree!("std::tuple::matcher_body" "push" sub_matchers; "push" tail_matcher),
})))
}
fn tuple_matcher_body(
children: HomoTpl<Expr>,
tail: OrcOpt<Expr>,
value: HomoTpl<Expr>,
) -> impl Future<Output = GExpr> {
exec(async move |mut h| -> OrcRes<OrcOpt<HomoTpl<Expr>>> {
if value.0.len() < children.0.len() {
return Ok(OrcOpt(None));
}
let mut binds = Vec::new();
for (sub_mat, sub_val) in children.0.iter().zip(&value.0) {
match match_one(&mut h, sub_mat.clone(), sub_val.clone()).await? {
OrcOpt(None) => return Ok(OrcOpt(None)),
OrcOpt(Some(subres)) => binds.extend(subres.0),
}
}
match tail.0 {
None if children.0.len() < value.0.len() => return Ok(OrcOpt(None)),
None => (),
Some(tail_mat) => {
let tail_tpl = stream::iter(&value.0[children.0.len()..])
.fold(sym!(std::tuple::empty).to_gen().await, async |prefix, new| {
call(sym!(std::tuple::cat), (prefix, new.clone())).await
})
.await;
match match_one(&mut h, tail_mat, tail_tpl).await? {
OrcOpt(Some(tail_binds)) => binds.extend(tail_binds.0),
OrcOpt(None) => return Ok(OrcOpt(None)),
}
},
};
Ok(OrcOpt(Some(HomoTpl(binds))))
})
}