Add type check error; Add parameter syntax

examples/clue_solver.ds

@@ -1,4 +1,4 @@
-all_cards = {
+all_cards <map> = {
 	rooms = ['Library' 'Kitchen' 'Conservatory']
 	suspects = ['White' 'Green' 'Scarlett']
 	weapons = ['Rope' 'Lead_Pipe' 'Knife']

src/abstract_tree/type.rs

@@ -30,28 +30,36 @@ impl Type {
             | (Type::Map, Type::Map)
             | (Type::String, Type::String)
             | (Type::Table, Type::Table) => Ok(()),
-            (Type::Boolean, _) => Err(Error::ExpectedBoolean {
+            (Type::Boolean, _) => Err(Error::TypeCheck {
+                expected: Type::Boolean,
                 actual: value.clone(),
             }),
-            (Type::Float, _) => Err(Error::ExpectedFloat {
+            (Type::Float, _) => Err(Error::TypeCheck {
+                expected: Type::Float,
                 actual: value.clone(),
             }),
-            (Type::Function, _) => Err(Error::ExpectedFunction {
+            (Type::Function, _) => Err(Error::TypeCheck {
+                expected: Type::Function,
                 actual: value.clone(),
             }),
-            (Type::Integer, _) => Err(Error::ExpectedInteger {
+            (Type::Integer, _) => Err(Error::TypeCheck {
+                expected: Type::Integer,
                 actual: value.clone(),
             }),
-            (Type::List, _) => Err(Error::ExpectedList {
+            (Type::List, _) => Err(Error::TypeCheck {
+                expected: Type::List,
                 actual: value.clone(),
             }),
-            (Type::Map, _) => Err(Error::ExpectedMap {
+            (Type::Map, _) => Err(Error::TypeCheck {
+                expected: Type::Map,
                 actual: value.clone(),
             }),
-            (Type::String, _) => Err(Error::ExpectedString {
+            (Type::String, _) => Err(Error::TypeCheck {
+                expected: Type::String,
                 actual: value.clone(),
             }),
-            (Type::Table, _) => Err(Error::ExpectedTable {
+            (Type::Table, _) => Err(Error::TypeCheck {
+                expected: Type::Table,
                 actual: value.clone(),
             }),
         }
@@ -76,7 +84,7 @@ impl AbstractTree for Type {
             "table" => Type::Table,
             _ => {
                 return Err(Error::UnexpectedSyntaxNode {
-                    expected: "bool, fn, int, list, map, string or table",
+                    expected: "any, bool, float, fn, int, list, map, str or table",
                     actual: node.kind(),
                     location: node.start_position(),
                     relevant_source: source[node.byte_range()].to_string(),

src/error.rs

@@ -5,7 +5,7 @@
 
 use tree_sitter::{Node, Point};
 
-use crate::{value::Value, Identifier};
+use crate::{value::Value, Identifier, Type};
 
 use std::{fmt, io, num::ParseFloatError, string::FromUtf8Error, sync::PoisonError, time};
 
@@ -20,6 +20,11 @@ pub enum Error {
         relevant_source: String,
     },
 
+    TypeCheck {
+        expected: Type,
+        actual: Value,
+    },
+
     /// The 'assert' macro did not resolve successfully.
     AssertEqualFailed {
         expected: Value,
@@ -351,6 +356,10 @@ impl fmt::Display for Error {
             Syntax { source, location } => {
                 write!(f, "Syntax error at {location}, this is not valid: {source}")
             }
+            TypeCheck { expected, actual } => write!(
+                f,
+                "Type check error. Expected a {expected} but got {actual}."
+            ),
         }
     }
 }

src/value/function.rs

@@ -20,32 +20,41 @@ impl Function {
 
 impl AbstractTree for Function {
     fn from_syntax_node(source: &str, node: Node) -> Result<Self> {
+        Error::expect_syntax_node(source, "function", node)?;
+
+        let child_count = node.child_count();
         let mut parameters = Vec::new();
-        let mut previous_identifier = None;
 
-        for index in 1..node.child_count() - 2 {
+        for index in 1..child_count - 2 {
-            let child = node.child(index).unwrap();
+            let parameter_node = {
+                let child = node.child(index).unwrap();
 
-            if child.kind() == "identifier" {
+                if child.is_named() {
-                previous_identifier = Some(Identifier::from_syntax_node(source, child)?);
+                    child
-            }
+                } else {
+                    continue;
+                }
+            };
 
-            if child.kind() == "type" {
+            Error::expect_syntax_node(source, "parameter", parameter_node)?;
-                let identifier = previous_identifier.take().unwrap();
-                let r#type = Type::from_syntax_node(source, child)?;
 
-                parameters.push((identifier, r#type))
+            let identifier_node = parameter_node.child(0).unwrap();
-            }
+            let identifier = Identifier::from_syntax_node(source, identifier_node)?;
+
+            let type_node = parameter_node.child(1).unwrap();
+            let r#type = Type::from_syntax_node(source, type_node)?;
+
+            parameters.push((identifier, r#type))
         }
 
-        let return_type_node = node.child_by_field_name("return_type");
+        let return_type_node = node.child(child_count - 2).unwrap();
-        let return_type = if let Some(child) = return_type_node {
+        let return_type = if return_type_node.is_named() {
-            Some(Type::from_syntax_node(source, child)?)
+            Some(Type::from_syntax_node(source, return_type_node)?)
         } else {
             None
         };
 
-        let body_node = node.child_by_field_name("body").unwrap();
+        let body_node = node.child(child_count - 1).unwrap();
         let body = Block::from_syntax_node(source, body_node)?;
 
         Ok(Function {

tree-sitter-dust/corpus/functions.txt

@@ -76,10 +76,12 @@ Complex Function
     (expression
       (value
         (function
-          (identifier)
+          (parameter
-          (type)
+            (identifier)
-          (identifier)
+            (type))
-          (type)
+          (parameter
+            (identifier)
+            (type))
           (block
             (statement
               (expression

tree-sitter-dust/grammar.js

@@ -276,13 +276,13 @@ module.exports = grammar({
   
     function: $ => seq(
       '|',
-      field('parameters', repeat($._function_parameters)),
+      repeat($.parameter),
       '|',
-      optional(field('return_type', $.type)),
+      optional($.type),
-      field('body', $.block),
+      $.block,
     ),
 
-    _function_parameters: $ => seq(
+    parameter: $ => seq(
       $.identifier,
       $.type,
       optional(','),

tree-sitter-dust/src/grammar.json

@@ -1166,7 +1166,7 @@
           "type": "REPEAT",
           "content": {
             "type": "SYMBOL",
-            "name": "_function_parameters"
+            "name": "parameter"
           }
         },
         {
@@ -1177,12 +1177,8 @@
           "type": "CHOICE",
           "members": [
             {
-              "type": "FIELD",
+              "type": "SYMBOL",
-              "name": "return_type",
+              "name": "type"
-              "content": {
-                "type": "SYMBOL",
-                "name": "type"
-              }
             },
             {
               "type": "BLANK"
@@ -1190,16 +1186,12 @@
           ]
         },
         {
-          "type": "FIELD",
+          "type": "SYMBOL",
-          "name": "body",
+          "name": "block"
-          "content": {
-            "type": "SYMBOL",
-            "name": "block"
-          }
         }
       ]
     },
-    "_function_parameters": {
+    "parameter": {
       "type": "SEQ",
       "members": [
         {

tree-sitter-dust/src/node-types.json

@@ -184,34 +184,17 @@
   {
     "type": "function",
     "named": true,
-    "fields": {
+    "fields": {},
-      "body": {
-        "multiple": false,
-        "required": true,
-        "types": [
-          {
-            "type": "block",
-            "named": true
-          }
-        ]
-      },
-      "return_type": {
-        "multiple": false,
-        "required": false,
-        "types": [
-          {
-            "type": "type",
-            "named": true
-          }
-        ]
-      }
-    },
     "children": {
       "multiple": true,
-      "required": false,
+      "required": true,
       "types": [
         {
-          "type": "identifier",
+          "type": "block",
+          "named": true
+        },
+        {
+          "type": "parameter",
           "named": true
         },
         {
@@ -455,6 +438,25 @@
     "named": true,
     "fields": {}
   },
+  {
+    "type": "parameter",
+    "named": true,
+    "fields": {},
+    "children": {
+      "multiple": true,
+      "required": true,
+      "types": [
+        {
+          "type": "identifier",
+          "named": true
+        },
+        {
+          "type": "type",
+          "named": true
+        }
+      ]
+    }
+  },
   {
     "type": "return",
     "named": true,