diff options
author | Basile Henry | 2020-11-01 23:14:12 +0100 |
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committer | Basile Henry | 2020-11-01 23:14:12 +0100 |
commit | aaac028d21b02827a0c79b34728fb104e5649149 (patch) | |
tree | 90b15689b8fa853dd8aff1803359a2e985f3581f /dhall/src/operations | |
parent | 6987b275e4bf5f545d823d186ce08a2fe9a3eb44 (diff) |
Implement normalization for With op
Diffstat (limited to 'dhall/src/operations')
-rw-r--r-- | dhall/src/operations/normalization.rs | 45 |
1 files changed, 43 insertions, 2 deletions
diff --git a/dhall/src/operations/normalization.rs b/dhall/src/operations/normalization.rs index b930f93..908ed93 100644 --- a/dhall/src/operations/normalization.rs +++ b/dhall/src/operations/normalization.rs @@ -4,7 +4,7 @@ use std::iter::once; use crate::operations::{BinOp, OpKind}; use crate::semantics::{ - merge_maps, ret_kind, ret_op, ret_ref, Nir, NirKind, Ret, TextLit, + merge_maps, ret_kind, ret_nir, ret_op, ret_ref, Nir, NirKind, Ret, TextLit, }; use crate::syntax::{ExprKind, Label, NumKind}; @@ -299,7 +299,48 @@ pub fn normalize_operation(opkind: &OpKind<Nir>) -> Ret { )), _ => nothing_to_do(), }, - Completion(..) | With(..) => { + With(record, labels, expr) => { + use std::iter::FromIterator; + + let mut current_nk: Option<NirKind> = Some(record.kind().clone()); + let mut visited: Vec<(&Label, HashMap<Label, Nir>)> = Vec::new(); + let mut to_create = Vec::new(); + + for label in labels { + match current_nk { + None => to_create.push(label), + Some(nk) => match nk { + RecordLit(kvs) => { + current_nk = + kvs.get(label).map(|nir| nir.kind().clone()); + visited.push((label, kvs)); + } + _ => return nothing_to_do(), + }, + } + } + + // Create Nir for record bottom up + let mut nir = expr.clone(); + + while let Some(label) = to_create.pop() { + let rec = RecordLit(FromIterator::from_iter(once(( + label.clone(), + nir, + )))); + nir = Nir::from_kind(rec); + } + + // Update visited records + while let Some((label, mut kvs)) = visited.pop() { + kvs.insert(label.clone(), nir); + let rec = RecordLit(kvs); + nir = Nir::from_kind(rec); + } + + ret_nir(nir) + } + Completion(..) => { unreachable!("This case should have been handled in resolution") } } |