language-servers/roc
1
0
Fork 0
mirror of https://github.com/roc-lang/roc.git synced 2025-09-30 15:21:12 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

clarify how we deal with a closure layout

Browse source
This commit is contained in:
Folkert 2020-10-18 21:04:58 +02:00
parent b26f778ee0
commit b0ef8b9b07
2 changed files with 60 additions and 31 deletions
Download patch file Download diff file Expand all files Collapse all files

1
compiler/gen/tests/gen_primitives.rs
View file

@ -1025,7 +1025,6 @@ mod gen_primitives {
main : Float
main =
runEffect foo
"#
),
3.14,

46
compiler/mono/src/ir.rs
View file

@ -1497,7 +1497,7 @@ fn build_specialized_proc<'a>(
layout_cache: &mut LayoutCache<'a>,
pattern_symbols: &[Symbol],
pattern_vars: &[Variable],
closure_layout: Option<ClosureLayout<'a>>,
opt_closure_layout: Option<ClosureLayout<'a>>,
ret_var: Variable,
) -> Result<(&'a [(Layout<'a>, Symbol)], Layout<'a>), LayoutProblem> {
let mut proc_args = Vec::with_capacity_in(pattern_vars.len(), &env.arena);
@ -1508,18 +1508,38 @@ fn build_specialized_proc<'a>(
proc_args.push((layout, *arg_name));
}
// is the final argument symbol the closure symbol? then add the closure variable to the
// pattern variables
if pattern_symbols.last() == Some(&Symbol::ARG_CLOSURE) {
let layout = closure_layout.unwrap().as_layout();
proc_args.push((layout, Symbol::ARG_CLOSURE));
// Given
//
// foo =
// x = 42
//
// f = \{} -> x
//
// We desugar that into
//
// f = \{}, x -> x
//
// foo =
// x = 42
//
// f_closure = { ptr: f, closure: x }
//
// then
match opt_closure_layout {
Some(layout) if pattern_symbols.last() == Some(&Symbol::ARG_CLOSURE) => {
// here we define the lifted (now top-level) f function. Its final argument is `Symbol::ARG_CLOSURE`,
// it stores the closure structure (just an integer in this case)
proc_args.push((layout.as_layout(), Symbol::ARG_CLOSURE));
debug_assert_eq!(
pattern_vars.len() + 1,
pattern_symbols.len(),
"Tried to zip two vecs with different lengths!"
);
} else if let Some(layout) = closure_layout {
}
Some(layout) => {
// else if there is a closure layout, we're building the `f_closure` value
// that means we're really creating a ( function_ptr, closure_data ) pair
let ret_layout = layout_cache
.from_var(&env.arena, ret_var, env.subs)
.unwrap_or_else(|err| panic!("TODO handle invalid function {:?}", err));
@ -1535,13 +1555,23 @@ fn build_specialized_proc<'a>(
Layout::Struct(env.arena.alloc([function_ptr_layout, closure_data_layout]));
return Ok((&[], closure_layout));
} else {
}
None => {
// else we're making a normal function, no closure problems to worry about
// we'll just assert some things
// make sure there is not arg_closure argument without a closure layout
debug_assert!(pattern_symbols.last() != Some(&Symbol::ARG_CLOSURE));
// since this is not a closure, the number of arguments should match between symbols
// and layout
debug_assert_eq!(
pattern_vars.len(),
pattern_symbols.len(),
"Tried to zip two vecs with different lengths!"
);
}
}
let proc_args = proc_args.into_bump_slice();