Correct grammar

corpus/tests.txt

@@ -52,14 +52,14 @@ x = y + y;
 
 (source_file
 	(expression
-		(identifier))
+        (identifier)
         (operator)
     (expression
-		(identifier))
+        (identifier)
         (operator)
     (expression
-		(identifier))
+        (identifier))))
-	(operator))
+	(chain))
 
 ==================
 String
@@ -70,7 +70,7 @@ String
 ---
 
 (source_file
-	(expression
+	(value
 		(string)))
 
 ==================
@@ -82,7 +82,7 @@ Integer
 ---
 
 (source_file
-	(expression
+	(value
 		(integer)))
 
 ==================
@@ -94,7 +94,7 @@ Float
 ---
 
 (source_file
-	(expression
+	(value
 		(float)))
 
 
@@ -107,12 +107,12 @@ List
 ---
 
 (source_file
-	(expression
+	(value
         (list
-          	(expression
+          	(value
-            	(integer))
+            	(integer)))
-          	(expression
+          	(value
-            	(integer)))))
+            	(integer))))
 
 ==================
 Empty
@@ -123,7 +123,7 @@ Empty
 ---
 
 (source_file
-	(expression
+	(value
 		(empty)))
 
 ==================
@@ -137,8 +137,8 @@ random_boolean();
 (source_file
 	(expression
 		(tool))
-	(expression
+	(value
 		(empty))
-	(operator))
+	(chain))
 
 

grammar.js

@@ -1,28 +1,42 @@
 module.exports = grammar({
-  name: 'dust',
+  name: 'Dust',
 
   rules: {
-    source_file: $ => repeat(choice($.comment, $.expression, $.operator)),
+    source_file: $ => repeat(choice(
+      $.comment, 
+      $.expression,
+      $.value,  
+      $.yield,
+      $.chain
+    )),
 
     comment: $ => /(#)(.+?)([\n\r])/,
 
     expression: $ => choice(
       $.identifier,
+      $.tool,
+      seq($.identifier, $.operator, $.expression),
+      seq($.value, $.operator, $.value)
+    ),
+
+    value: $ => choice(
       $.integer,
       $.float,
       $.string,
       $.list,
-      $.tool,
       $.empty,
     ),
 
+    yield: $ => "->",
+
+    chain: $ => ";",
+    
     identifier: $ => /[a-zA-Z|_|.]+(_[a-zA-Z]+)*/,
 
     operator: $ => choice(
       '=',
       '-',
       '+',
-      ';',
       '/',
       '|',
       '&'

src/grammar.json

@@ -1,5 +1,5 @@
 {
-  "name": "dust",
+  "name": "Dust",
   "rules": {
     "source_file": {
       "type": "REPEAT",
@@ -16,7 +16,15 @@
           },
           {
             "type": "SYMBOL",
-            "name": "operator"
+            "name": "value"
+          },
+          {
+            "type": "SYMBOL",
+            "name": "yield"
+          },
+          {
+            "type": "SYMBOL",
+            "name": "chain"
           }
         ]
       }
@@ -32,6 +40,49 @@
           "type": "SYMBOL",
           "name": "identifier"
         },
+        {
+          "type": "SYMBOL",
+          "name": "tool"
+        },
+        {
+          "type": "SEQ",
+          "members": [
+            {
+              "type": "SYMBOL",
+              "name": "identifier"
+            },
+            {
+              "type": "SYMBOL",
+              "name": "operator"
+            },
+            {
+              "type": "SYMBOL",
+              "name": "expression"
+            }
+          ]
+        },
+        {
+          "type": "SEQ",
+          "members": [
+            {
+              "type": "SYMBOL",
+              "name": "value"
+            },
+            {
+              "type": "SYMBOL",
+              "name": "operator"
+            },
+            {
+              "type": "SYMBOL",
+              "name": "value"
+            }
+          ]
+        }
+      ]
+    },
+    "value": {
+      "type": "CHOICE",
+      "members": [
         {
           "type": "SYMBOL",
           "name": "integer"
@@ -48,16 +99,20 @@
           "type": "SYMBOL",
           "name": "list"
         },
-        {
-          "type": "SYMBOL",
-          "name": "tool"
-        },
         {
           "type": "SYMBOL",
           "name": "empty"
         }
       ]
     },
+    "yield": {
+      "type": "STRING",
+      "value": "->"
+    },
+    "chain": {
+      "type": "STRING",
+      "value": ";"
+    },
     "identifier": {
       "type": "PATTERN",
       "value": "[a-zA-Z|_|.]+(_[a-zA-Z]+)*"
@@ -77,10 +132,6 @@
           "type": "STRING",
           "value": "+"
         },
-        {
-          "type": "STRING",
-          "value": ";"
-        },
         {
           "type": "STRING",
           "value": "/"

src/node-types.json

@@ -4,15 +4,11 @@
     "named": true,
     "fields": {},
     "children": {
-      "multiple": false,
+      "multiple": true,
       "required": true,
       "types": [
         {
-          "type": "empty",
+          "type": "expression",
-          "named": true
-        },
-        {
-          "type": "float",
           "named": true
         },
         {
@@ -20,20 +16,16 @@
           "named": true
         },
         {
-          "type": "integer",
+          "type": "operator",
-          "named": true
-        },
-        {
-          "type": "list",
-          "named": true
-        },
-        {
-          "type": "string",
           "named": true
         },
         {
           "type": "tool",
           "named": true
+        },
+        {
+          "type": "value",
+          "named": true
         }
       ]
     }
@@ -66,6 +58,10 @@
       "multiple": true,
       "required": false,
       "types": [
+        {
+          "type": "chain",
+          "named": true
+        },
         {
           "type": "comment",
           "named": true
@@ -75,7 +71,11 @@
           "named": true
         },
         {
-          "type": "operator",
+          "type": "value",
+          "named": true
+        },
+        {
+          "type": "yield",
           "named": true
         }
       ]
@@ -86,6 +86,37 @@
     "named": true,
     "fields": {}
   },
+  {
+    "type": "value",
+    "named": true,
+    "fields": {},
+    "children": {
+      "multiple": false,
+      "required": true,
+      "types": [
+        {
+          "type": "empty",
+          "named": true
+        },
+        {
+          "type": "float",
+          "named": true
+        },
+        {
+          "type": "integer",
+          "named": true
+        },
+        {
+          "type": "list",
+          "named": true
+        },
+        {
+          "type": "string",
+          "named": true
+        }
+      ]
+    }
+  },
   {
     "type": "&",
     "named": false
@@ -115,12 +146,12 @@
     "named": false
   },
   {
-    "type": ";",
+    "type": "=",
     "named": false
   },
   {
-    "type": "=",
+    "type": "chain",
-    "named": false
+    "named": true
   },
   {
     "type": "comment",
@@ -166,6 +197,10 @@
     "type": "string",
     "named": true
   },
+  {
+    "type": "yield",
+    "named": true
+  },
   {
     "type": "|",
     "named": false