From bfbc1580aa99fc108ff4ceb256447f837cb63d8c Mon Sep 17 00:00:00 2001
From: greg <greg.shuflin@protonmail.com>
Date: Tue, 30 Oct 2018 23:36:55 -0700
Subject: [PATCH] Make tag optional

---
 schala-lang/language/src/reduced_ast.rs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/schala-lang/language/src/reduced_ast.rs b/schala-lang/language/src/reduced_ast.rs
index 8189ae6..1bfdef0 100644
--- a/schala-lang/language/src/reduced_ast.rs
+++ b/schala-lang/language/src/reduced_ast.rs
@@ -202,12 +202,12 @@ fn reduce_if_expression(discriminator: &Discriminator, body: &IfExpressionBody,
  * x is SomeBigOldEnum(_, x, Some(t))
  */
 
-fn handle_symbol(symbol: &Symbol, subpatterns: &Vec<Pattern>) -> Subpattern {
+fn handle_symbol(symbol: Option<&Symbol>, subpatterns: &Vec<Pattern>) -> Subpattern {
   use self::Pattern::*;
-  let tag = match symbol.spec {
+  let tag = symbol.map(|symbol| match symbol.spec {
     SymbolSpec::DataConstructor { index, .. } => index.clone(),
     _ => panic!("Symbol is not a data constructor - this should've been caught in type-checking"),
-  };
+  });
   let bound_vars = subpatterns.iter().map(|p| match p {
     Literal(PatternLiteral::VarPattern(var)) => Some(var.clone()),
     _ => None,
@@ -226,7 +226,7 @@ fn handle_symbol(symbol: &Symbol, subpatterns: &Vec<Pattern>) -> Subpattern {
   let subpatterns = vec![];
 
   Subpattern {
-    tag: Some(tag),
+    tag,
     subpatterns,
     guard,
     bound_vars,
@@ -239,7 +239,7 @@ impl Pattern {
     match self {
       TupleStruct(name, subpatterns) => {
         let symbol = symbol_table.lookup_by_name(name).expect(&format!("Symbol {} not found", name));
-        let s = handle_symbol(symbol, subpatterns);
+        let s = handle_symbol(Some(symbol), subpatterns);
         Alternative {
           tag: s.tag,
           subpatterns: s.subpatterns,
@@ -310,7 +310,7 @@ impl PatternLiteral {
         }
       },
       VarPattern(var) => match symbol_table.lookup_by_name(var) {
-        Some(symbol) => handle_symbol(symbol, &vec![]),
+        Some(symbol) => handle_symbol(Some(symbol), &vec![]),
         None => Subpattern {
           tag: None,
           subpatterns: vec![],