From a0a9bc2fdfbe23857c85206374b885f3b3dc5b68 Mon Sep 17 00:00:00 2001
From: Jeff <dev@jeffa.io>
Date: Sun, 24 Mar 2024 10:58:09 -0400
Subject: [PATCH] Add type arguments to function calls

---
 dust-lang/src/abstract_tree/function_call.rs |  3 +
 dust-lang/src/parser.rs                      | 61 ++++++++++++++++----
 dust-lang/src/value.rs                       |  4 +-
 3 files changed, 55 insertions(+), 13 deletions(-)

diff --git a/dust-lang/src/abstract_tree/function_call.rs b/dust-lang/src/abstract_tree/function_call.rs
index 1416c2f..1e0b1cb 100644
--- a/dust-lang/src/abstract_tree/function_call.rs
+++ b/dust-lang/src/abstract_tree/function_call.rs
@@ -9,16 +9,19 @@ use super::{AbstractNode, Action, Expression, Type, WithPosition};
 #[derive(Debug, Clone, Eq, PartialEq, PartialOrd, Ord)]
 pub struct FunctionCall {
     function: Box<WithPosition<Expression>>,
+    type_arguments: Vec<WithPosition<Type>>,
     arguments: Vec<WithPosition<Expression>>,
 }
 
 impl FunctionCall {
     pub fn new(
         function: WithPosition<Expression>,
+        type_arguments: Vec<WithPosition<Type>>,
         arguments: Vec<WithPosition<Expression>>,
     ) -> Self {
         FunctionCall {
             function: Box::new(function),
+            type_arguments,
             arguments,
         }
     }
diff --git a/dust-lang/src/parser.rs b/dust-lang/src/parser.rs
index 8351be5..0500ced 100644
--- a/dust-lang/src/parser.rs
+++ b/dust-lang/src/parser.rs
@@ -291,6 +291,20 @@ pub fn parser<'src>() -> impl Parser<
                         .with_position(state.span())
                 });
 
+            let turbofish = r#type
+                .clone()
+                .separated_by(just(Token::Control(Control::Comma)))
+                .at_least(1)
+                .collect()
+                .delimited_by(
+                    just(Token::Control(Control::ParenOpen)),
+                    just(Token::Control(Control::ParenClose)),
+                )
+                .delimited_by(
+                    just(Token::Control(Control::DoubleColon)),
+                    just(Token::Control(Control::DoubleColon)),
+                );
+
             let atom = choice((
                 range.clone(),
                 structure_instance.clone(),
@@ -323,17 +337,28 @@ pub fn parser<'src>() -> impl Parser<
                 ),
                 postfix(
                     3,
-                    positioned_expression
-                        .clone()
-                        .separated_by(just(Token::Control(Control::Comma)))
-                        .collect()
-                        .delimited_by(
-                            just(Token::Control(Control::ParenOpen)),
-                            just(Token::Control(Control::ParenClose)),
-                        ),
-                    |function_expression, arguments, span| {
-                        Expression::FunctionCall(FunctionCall::new(function_expression, arguments))
-                            .with_position(span)
+                    turbofish.clone().or_not().then(
+                        positioned_expression
+                            .clone()
+                            .separated_by(just(Token::Control(Control::Comma)))
+                            .collect()
+                            .delimited_by(
+                                just(Token::Control(Control::ParenOpen)),
+                                just(Token::Control(Control::ParenClose)),
+                            ),
+                    ),
+                    |function_expression,
+                     (type_arguments, arguments): (
+                        Option<Vec<WithPosition<Type>>>,
+                        Vec<WithPosition<Expression>>,
+                    ),
+                     span| {
+                        Expression::FunctionCall(FunctionCall::new(
+                            function_expression,
+                            type_arguments.unwrap_or_else(|| Vec::with_capacity(0)),
+                            arguments,
+                        ))
+                        .with_position(span)
                     },
                 ),
                 infix(
@@ -690,6 +715,7 @@ mod tests {
                 vec![
                     Statement::Expression(Expression::FunctionCall(FunctionCall::new(
                         Expression::Identifier(Identifier::new("output")).with_position((13, 19)),
+                        Vec::with_capacity(0),
                         vec![Expression::Value(ValueNode::String("hi".to_string()))
                             .with_position((20, 24))]
                     )))
@@ -793,6 +819,19 @@ mod tests {
                 )))
                 .with_position((0, 13)),
                 Vec::with_capacity(0),
+                Vec::with_capacity(0),
+            )))
+        )
+    }
+
+    #[test]
+    fn function_call_with_type_arguments() {
+        assert_eq!(
+            parse(&lex("foobar::(str)::('hi')").unwrap()).unwrap()[0].node,
+            Statement::Expression(Expression::FunctionCall(FunctionCall::new(
+                Expression::Identifier(Identifier::new("foobar")).with_position((0, 6)),
+                vec![Type::String.with_position((9, 12))],
+                vec![Expression::Value(ValueNode::String("hi".to_string())).with_position((16, 20))],
             )))
         )
     }
diff --git a/dust-lang/src/value.rs b/dust-lang/src/value.rs
index 4f3a9f5..f6f35a7 100644
--- a/dust-lang/src/value.rs
+++ b/dust-lang/src/value.rs
@@ -51,8 +51,8 @@ impl Value {
         Value(Arc::new(ValueInner::Range(range)))
     }
 
-    pub fn string(string: String) -> Self {
-        Value(Arc::new(ValueInner::String(string)))
+    pub fn string<T: ToString>(to_string: T) -> Self {
+        Value(Arc::new(ValueInner::String(to_string.to_string())))
     }
 
     pub fn function(