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authorNadrieril2019-03-06 16:30:40 +0100
committerNadrieril2019-03-06 16:30:40 +0100
commit4d92f06c98c98c014a02c218b6c31cf81d9f0fec (patch)
tree30a2e3e0879c58c866a3ae0ed7cbebf2c4a1cfa6 /dhall/src
parent45992d093b950170fc30e63d2c7d7a2767e9b9e8 (diff)
Move context to dhall_core
Diffstat (limited to 'dhall/src')
-rw-r--r--dhall/src/context.rs56
-rw-r--r--dhall/src/lib.rs1
-rw-r--r--dhall/src/typecheck.rs2
3 files changed, 1 insertions, 58 deletions
diff --git a/dhall/src/context.rs b/dhall/src/context.rs
deleted file mode 100644
index b88a677..0000000
--- a/dhall/src/context.rs
+++ /dev/null
@@ -1,56 +0,0 @@
-use std::collections::HashMap;
-
-/// A `(Context a)` associates `Text` labels with values of type `a`
-///
-/// The `Context` is used for type-checking when `(a = Expr X)`
-///
-/// * You create a `Context` using `empty` and `insert`
-/// * You transform a `Context` using `fmap`
-/// * You consume a `Context` using `lookup` and `toList`
-///
-/// The difference between a `Context` and a `Map` is that a `Context` lets you
-/// have multiple ordered occurrences of the same key and you can query for the
-/// `n`th occurrence of a given key.
-///
-#[derive(Debug, Clone)]
-pub struct Context<'i, T>(HashMap<&'i str, Vec<T>>);
-
-impl<'i, T> Context<'i, T> {
- /// An empty context with no key-value pairs
- pub fn new() -> Self {
- Context(HashMap::new())
- }
-
- /// Look up a key by name and index
- ///
- /// ```c
- /// lookup _ _ empty = Nothing
- /// lookup k 0 (insert k v c) = Just v
- /// lookup k n (insert k v c) = lookup k (n - 1) c -- 1 <= n
- /// lookup k n (insert j v c) = lookup k n c -- k /= j
- /// ```
- pub fn lookup<'a>(&'a self, k: &str, n: usize) -> Option<&'a T> {
- self.0.get(k).and_then(|v| v.get(v.len() - 1 - n))
- }
-
- pub fn map<U, F: Fn(&T) -> U>(&self, f: F) -> Context<'i, U> {
- Context(
- self.0
- .iter()
- .map(|(k, v)| (*k, v.iter().map(&f).collect()))
- .collect(),
- )
- }
-}
-
-impl<'i, T: Clone> Context<'i, T> {
- /// Add a key-value pair to the `Context`
- pub fn insert(&self, k: &'i str, v: T) -> Self {
- let mut ctx = (*self).clone();
- {
- let m = ctx.0.entry(k).or_insert_with(Vec::new);
- m.push(v);
- }
- ctx
- }
-}
diff --git a/dhall/src/lib.rs b/dhall/src/lib.rs
index 902df53..32662cd 100644
--- a/dhall/src/lib.rs
+++ b/dhall/src/lib.rs
@@ -1,5 +1,4 @@
#![feature(box_patterns)]
#![feature(trace_macros)]
-pub mod context;
pub mod typecheck;
diff --git a/dhall/src/typecheck.rs b/dhall/src/typecheck.rs
index 26192d2..aa8aa08 100644
--- a/dhall/src/typecheck.rs
+++ b/dhall/src/typecheck.rs
@@ -3,7 +3,7 @@ use std::collections::BTreeMap;
use std::collections::HashSet;
use std::fmt;
-use crate::context::Context;
+use dhall_core::context::Context;
use dhall_core::core;
use dhall_core::core::Builtin::*;
use dhall_core::core::Const::*;