Introduce LitKind to factor out common enum nodes

2 files changed, 26 insertions, 15 deletions

diff --git a/dhall/src/syntax/text/parser.rs b/dhall/src/syntax/text/parser.rs
index 0ff1363..f3ebd2b 100644
--- a/dhall/src/syntax/text/parser.rs
+++ b/dhall/src/syntax/text/parser.rs
@@ -7,6 +7,7 @@ use pest_consume::{match_nodes, Parser};
 
 use crate::syntax::map::{DupTreeMap, DupTreeSet};
 use crate::syntax::ExprKind::*;
+use crate::syntax::LitKind::*;
 use crate::syntax::{
     Double, Expr, FilePath, FilePrefix, Hash, ImportLocation, ImportMode,
     Integer, InterpolatedText, InterpolatedTextContents, Label, NaiveDouble,
@@ -344,8 +345,8 @@ impl DhallParser {
         let e = match crate::syntax::Builtin::parse(s) {
             Some(b) => Builtin(b),
             None => match s {
-                "True" => BoolLit(true),
-                "False" => BoolLit(false),
+                "True" => Lit(Bool(true)),
+                "False" => Lit(Bool(false)),
                 "Type" => Const(crate::syntax::Const::Type),
                 "Kind" => Const(crate::syntax::Const::Kind),
                 "Sort" => Const(crate::syntax::Const::Sort),
@@ -833,9 +834,9 @@ impl DhallParser {
     #[alias(expression, shortcut = true)]
     fn primitive_expression(input: ParseInput) -> ParseResult<Expr> {
         Ok(match_nodes!(input.children();
-            [double_literal(n)] => spanned(input, DoubleLit(n)),
-            [natural_literal(n)] => spanned(input, NaturalLit(n)),
-            [integer_literal(n)] => spanned(input, IntegerLit(n)),
+            [double_literal(n)] => spanned(input, Lit(Double(n))),
+            [natural_literal(n)] => spanned(input, Lit(Natural(n))),
+            [integer_literal(n)] => spanned(input, Lit(Integer(n))),
             [double_quote_literal(s)] => spanned(input, TextLit(s)),
             [single_quote_literal(s)] => spanned(input, TextLit(s)),
             [record_type_or_literal(e)] => spanned(input, e),
diff --git a/dhall/src/syntax/text/printer.rs b/dhall/src/syntax/text/printer.rs
index d1c9588..8891d41 100644
--- a/dhall/src/syntax/text/printer.rs
+++ b/dhall/src/syntax/text/printer.rs
@@ -196,15 +196,7 @@ impl<SE: Display + Clone> Display for ExprKind<SE> {
             Var(a) => a.fmt(f)?,
             Const(k) => k.fmt(f)?,
             Builtin(v) => v.fmt(f)?,
-            BoolLit(true) => f.write_str("True")?,
-            BoolLit(false) => f.write_str("False")?,
-            NaturalLit(a) => a.fmt(f)?,
-            IntegerLit(a) if *a >= 0 => {
-                f.write_str("+")?;
-                a.fmt(f)?;
-            }
-            IntegerLit(a) => a.fmt(f)?,
-            DoubleLit(a) => a.fmt(f)?,
+            Lit(a) => a.fmt(f)?,
             TextLit(a) => a.fmt(f)?,
             RecordType(a) if a.is_empty() => f.write_str("{}")?,
             RecordType(a) => fmt_list("{ ", ", ", " }", a, f, |(k, t), f| {
@@ -239,7 +231,25 @@ impl<SE: Display + Clone> Display for ExprKind<SE> {
 
 impl Display for Expr {
     fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-        self.as_ref().fmt_phase(f, PrintPhase::Base)
+        self.kind().fmt_phase(f, PrintPhase::Base)
+    }
+}
+
+impl Display for LitKind {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        use LitKind::*;
+        match self {
+            Bool(true) => f.write_str("True")?,
+            Bool(false) => f.write_str("False")?,
+            Natural(a) => a.fmt(f)?,
+            Integer(a) if *a >= 0 => {
+                f.write_str("+")?;
+                a.fmt(f)?;
+            }
+            Integer(a) => a.fmt(f)?,
+            Double(a) => a.fmt(f)?,
+        }
+        Ok(())
     }
 }