From 1b517b872348839bce16235db3bfcd3d865744d0 Mon Sep 17 00:00:00 2001
From: ProgramSnail <PurpureBacterium@yandex.ru>
Date: Sun, 23 Jul 2023 19:40:38 +0300
Subject: [PATCH] minor fixes

---
 corpus/test.langexp | 51 ++++++++++++++++++++++++---------------------
 grammar.g4          |  4 ++--
 grammar.js          | 10 ++++-----
 3 files changed, 34 insertions(+), 31 deletions(-)

diff --git a/corpus/test.langexp b/corpus/test.langexp
index 4b3e72f..f5ace2a 100644
--- a/corpus/test.langexp
+++ b/corpus/test.langexp
@@ -219,6 +219,7 @@ arg_deduction_example 'name 'duration : <- String <- Float -> Task = Task 'name
   (import
     (simple_name_identifier))
   (import
+    (placeholder)
     (simple_name_identifier))
   (import
     (simple_name_identifier)
@@ -635,13 +636,14 @@ arg_deduction_example 'name 'duration : <- String <- Float -> Task = Task 'name
         (simple_name_identifier))))
   (type_definition
     (simple_type_identifier)
-    (tuple_type
-      (annotation_identifier)
-      (type
-        (simple_type_identifier))
-      (annotation_identifier)
-      (type
-        (simple_type_identifier))))
+    (variant_type
+      (tuple_type
+        (annotation_identifier)
+        (type
+          (simple_type_identifier))
+        (annotation_identifier)
+        (type
+          (simple_type_identifier)))))
   (type_definition
     (simple_type_identifier)
     (variant_type
@@ -800,27 +802,28 @@ arg_deduction_example 'name 'duration : <- String <- Float -> Task = Task 'name
     (simple_type_identifier)
     (argument_type_identifier)
     (argument_type_identifier)
-    (tuple_type
-      (annotation_identifier)
-      (type
-        (simple_type_identifier))
-      (annotation_identifier)
-      (type
-        (simple_type_identifier))
-      (annotation_identifier)
-      (type
-        (simple_type_identifier)
+    (variant_type
+      (tuple_type
+        (annotation_identifier)
         (type
-          (argument_type_identifier))
+          (simple_type_identifier))
+        (annotation_identifier)
         (type
-          (argument_type_identifier)))
-      (annotation_identifier)
-      (type
-        (simple_type_identifier)
+          (simple_type_identifier))
+        (annotation_identifier)
         (type
-          (argument_type_identifier))
+          (simple_type_identifier)
+          (type
+            (argument_type_identifier))
+          (type
+            (argument_type_identifier)))
+        (annotation_identifier)
         (type
-          (argument_type_identifier)))))
+          (simple_type_identifier)
+          (type
+            (argument_type_identifier))
+          (type
+            (argument_type_identifier))))))
   (type_definition
     (simple_type_identifier)
     (function_definition
diff --git a/grammar.g4 b/grammar.g4
index c952ef2..b6401cb 100644
--- a/grammar.g4
+++ b/grammar.g4
@@ -18,7 +18,7 @@ import: ('::' | 'import') (SIMPLE_NAME_IDENTIFIER | '_') ('=' SIMPLE_NAME_IDENTI
 constraint: '?' expression ;
 
 type_definition: (DEFINITION_INFO)? (ANNOTATION_INFO)* ('^')?
-                 SIMPLE_TYPE_IDENTIFIER ((ARGUMENT_TYPE_IDENTIFIER)* '=' (variant_type | typle_type))?
+                 SIMPLE_TYPE_IDENTIFIER ((ARGUMENT_TYPE_IDENTIFIER)* '=' variant_type)?
                  (('{' function_definietion '}')|';')
                  ;
 
@@ -122,7 +122,7 @@ not_name_scoped_expression: block
                           | '(' super_expression ')'
                           ;
 
-variant_type: ('|')? tuple_type ('|' tuple_type)+ ;
+variant_type: ('|')? tuple_type ('|' tuple_type)* ;
 
 tuple_type: ('&')? annotated_type ('&' _annotated_type)* ;
 
diff --git a/grammar.js b/grammar.js
index 5b482b6..f2ca4a5 100644
--- a/grammar.js
+++ b/grammar.js
@@ -25,7 +25,7 @@ module.exports = grammar({
 
     import: $ => seq(
       choice('::', 'import'),
-      field('name', choice($.simple_name_identifier, '_')),
+      field('name', choice($.simple_name_identifier, $.placeholder)),
       optional(seq('=', field('module', $.simple_name_identifier))),
       optional(seq(':', repeat1(choice(
         $.simple_type_identifier,
@@ -45,7 +45,7 @@ module.exports = grammar({
       repeat($.annotation_info),
       optional('^'),
       field('name', $.simple_type_identifier),
-      optional(seq(repeat($.argument_type_identifier), '=', choice($.variant_type, $.tuple_type))),
+      optional(seq(repeat($.argument_type_identifier), '=', $.variant_type)),
       choice(seq('{', repeat($.function_definition), '}'), ';')
     ),
 
@@ -53,7 +53,7 @@ module.exports = grammar({
       optional($.definition_info),
       repeat($.annotation_info),
       repeat(seq($.constraint, ';')),
-      /*optional(seq(*/optional($._var_let)/*, '.'))*/,
+      optional($._var_let),
       choice(field('name', $.simple_name_identifier), seq('(', field('name', $.operator), ')')),
       repeat(seq(
         optional($.annotation_identifier),
@@ -71,7 +71,7 @@ module.exports = grammar({
 
     typeclass_definition: $ => seq(
       optional($.definition_info),
-      repeat($.annotation_info),
+      // no argumenmts => no annotation info
       field('name', $.typeclass_identifier),
       optional(seq(':', repeat1($.typeclass_identifier))),
       choice(seq('{', repeat($.function_definition), '}'), ';'),
@@ -218,7 +218,7 @@ module.exports = grammar({
     variant_type: $ => seq(
       optional('|'),
       $.tuple_type,
-      repeat1(seq('|', $.tuple_type)),
+      repeat(seq('|', $.tuple_type)),
     ),
 
     tuple_type: $ => seq(