Continue fixing built-in functions

dust-lang/src/abstract_tree/built_in_function.rs

@@ -35,7 +35,11 @@ impl BuiltInFunction {
         }
     }
 
-    pub fn call(&self, context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    pub fn call(
+        &self,
+        context: &Context,
+        manage_memory: bool,
+    ) -> Result<Option<Value>, RuntimeError> {
         match self {
             BuiltInFunction::Length => Length::call(context, manage_memory),
             BuiltInFunction::ReadLine => ReadLine::call(context, manage_memory),
@@ -49,7 +53,7 @@ impl BuiltInFunction {
 
 trait FunctionLogic {
     fn r#type() -> Type;
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError>;
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError>;
 }
 
 #[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
@@ -67,7 +71,7 @@ impl FunctionLogic for Length {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
         let value = if let Some(value) = context.get_value(&Identifier::new("input"))? {
             value
         } else {
@@ -83,7 +87,7 @@ impl FunctionLogic for Length {
             ));
         };
 
-        Ok(Value::integer(list.len() as i64))
+        Ok(Some(Value::integer(list.len() as i64)))
     }
 }
 
@@ -95,11 +99,11 @@ impl FunctionLogic for ReadFile {
         Type::Function {
             type_parameters: None,
             value_parameters: None,
-            return_type: None,
+            return_type: Some(Box::new(Type::String)),
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
         todo!()
     }
 }
@@ -112,11 +116,11 @@ impl FunctionLogic for ReadLine {
         Type::Function {
             type_parameters: None,
             value_parameters: None,
-            return_type: None,
+            return_type: Some(Box::new(Type::String)),
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
         todo!()
     }
 }
@@ -133,7 +137,7 @@ impl FunctionLogic for Sleep {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
         todo!()
     }
 }
@@ -150,7 +154,7 @@ impl FunctionLogic for WriteLine {
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
         todo!()
     }
 }
@@ -163,11 +167,14 @@ impl FunctionLogic for JsonParse {
         Type::Function {
             type_parameters: None,
             value_parameters: None,
-            return_type: None,
+            return_type: Some(Box::new(Type::Generic {
+                identifier: Identifier::new("T"),
+                concrete_type: None,
+            })),
         }
     }
 
-    fn call(context: &Context, manage_memory: bool) -> Result<Value, RuntimeError> {
+    fn call(context: &Context, manage_memory: bool) -> Result<Option<Value>, RuntimeError> {
         let target_type = if let Some(r#type) = context.get_type(&Identifier::new("T"))? {
             r#type
         } else {
@@ -216,6 +223,6 @@ impl FunctionLogic for JsonParse {
             Ok(value)
         }
 
-        parse_value(&input, target_type)
+        parse_value(&input, target_type).map(|value| Some(value))
     }
 }

dust-lang/src/abstract_tree/function_call.rs

@@ -6,7 +6,7 @@ use crate::{
     value::ValueInner,
 };
 
-use super::{AbstractNode, Evaluation, Expression, Type, TypeConstructor};
+use super::{AbstractNode, Evaluation, Expression, Type, TypeConstructor, ValueNode, WithPosition};
 
 #[derive(Debug, Clone, Eq, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
 pub struct FunctionCall {
@@ -47,6 +47,14 @@ impl AbstractNode for FunctionCall {
     }
 
     fn validate(&self, context: &Context, manage_memory: bool) -> Result<(), ValidationError> {
+        if let Expression::Value(WithPosition {
+            node: ValueNode::BuiltInFunction(_),
+            ..
+        }) = self.function_expression.as_ref()
+        {
+            return Ok(());
+        }
+
         self.function_expression.validate(context, manage_memory)?;
 
         if let Some(value_arguments) = &self.value_arguments {

dust-lang/src/abstract_tree/value_node.rs

@@ -173,6 +173,8 @@ impl AbstractNode for ValueNode {
         {
             body.node.validate(&context_template, _manage_memory)?;
 
+            println!("beep");
+
             let ((expected_return, expected_position), actual_return) =
                 match (return_type, body.node.expected_type(&context_template)?) {
                     (Some(constructor), Some(r#type)) => (
@@ -372,7 +374,9 @@ impl AbstractNode for ValueNode {
                 Value::structure(name, fields)
             }
             ValueNode::BuiltInFunction(built_in_function) => {
-                built_in_function.call(context, manage_memory)?
+                return built_in_function
+                    .call(context, manage_memory)
+                    .map(|value_option| value_option.map(|value| Evaluation::Return(value)));
             }
         };
 

dust-lang/src/lib.rs

@@ -109,12 +109,10 @@ impl Interpreter {
     }
 
     pub fn load_std(&self) -> Result<(), InterpreterError> {
-        let std_core_source: (Arc<str>, Arc<str>) = {
+        let std_core_source: (Arc<str>, Arc<str>) = (
-            (
             Arc::from("std/core.ds"),
             Arc::from(include_str!("../../std/core.ds")),
-            )
+        );
-        };
         let std_sources: [(Arc<str>, Arc<str>); 4] = [
             (
                 Arc::from("std/fs.ds"),
@@ -172,7 +170,6 @@ impl Interpreter {
     ) -> Result<Option<Value>, InterpreterError> {
         let mut sources = self.sources.write().unwrap();
 
-        sources.clear();
         sources.push((source_id.clone(), source.clone()));
 
         let tokens = lex(source.as_ref()).map_err(|errors| InterpreterError {
@@ -431,7 +428,10 @@ impl InterpreterError {
                             .with_message(format!("This has type {}.", index_type.fg(type_color),)),
                         ])
                     }
-                    ValidationError::ExpectedExpression(_) => todo!(),
+                    ValidationError::ExpectedExpression(position) => builder.add_label(
+                        Label::new((self.source_id.clone(), position.0..position.1))
+                            .with_message("Expected a statement that ends in an expression."),
+                    ),
                     ValidationError::ExpectedFunction { .. } => todo!(),
                     ValidationError::ExpectedValue(_) => todo!(),
                     ValidationError::FieldNotFound {

std/io.ds

@@ -1,9 +1,9 @@
 io = {
 	read_line = fn () -> str {
-		__READ_LINE__
+		__READ_LINE__()
 	}
 
 	write_line = fn (output: any) {
-		__WRITE_LINE__ output
+		__WRITE_LINE__(output)
 	}
 }

std/json.ds

@@ -1,5 +1,5 @@
 json = {
 	parse = fn |T| (input: str) -> T {
-		__JSON_PARSE__ T input
+		__JSON_PARSE__::(T)::(input)
 	}
 }

std/thread.ds

@@ -1,5 +1,5 @@
 thread = {
 	sleep = fn (milliseconds: int) {
-		__SLEEP__ milliseconds
+		__SLEEP__(milliseconds)
 	}
 }