feat: support bare name assignments in interactive and function scopes

crates/frontend/src/ast/generated.rs

@@ -3,7 +3,7 @@
 use super::Spanned;
 use crate::Span;
 pub const AST_SCHEMA_ID: &str =
-    "urn:endor:ast:sha256:c0da1a2640ad85f2c8e8159a10756e649d3aab179823a7cd890d9ebbb7f5d46e";
+    "urn:endor:ast:sha256:8c89fde6c029357a0809751c41cb46d59972b987bbe1b25c0cced4bfcdbe2a7b";
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 #[serde(deny_unknown_fields)]
 pub struct AstDocument {
@@ -123,6 +123,7 @@ impl Spanned for Stmt {
 #[serde(tag = "kind", content = "data", deny_unknown_fields)]
 pub enum StmtKind {
     Binding(Binding),
+    Assignment(Assignment),
     Return(ReturnStatement),
     Expression(Expr),
     Declaration(Decl),
@@ -131,6 +132,7 @@ impl Spanned for StmtKind {
     fn span(&self) -> Span {
         match self {
             Self::Binding(node) => node.span(),
+            Self::Assignment(node) => node.span(),
             Self::Return(node) => node.span(),
             Self::Expression(node) => node.span(),
             Self::Declaration(node) => node.span(),
@@ -151,6 +153,18 @@ impl Spanned for Binding {
 }
 #[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
 #[serde(deny_unknown_fields)]
+pub struct Assignment {
+    pub name: Name,
+    pub value: Expr,
+    pub span: Span,
+}
+impl Spanned for Assignment {
+    fn span(&self) -> Span {
+        self.span
+    }
+}
+#[derive(Debug, Clone, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+#[serde(deny_unknown_fields)]
 pub struct ReturnStatement {
     pub value: Option<Expr>,
     pub span: Span,

crates/frontend/src/ast/visitor.rs

@@ -1,8 +1,9 @@
 // Generated by scripts/generate_ast.py from Endor.asdl. Do not edit.
 
 use super::{
-    AstDocument, AstRoot, BinaryOp, Binding, Block, Decl, DeclKind, Expr, ExprKind, Function,
-    InteractiveInput, Name, Parameter, Program, ReturnStatement, Spanned, Stmt, StmtKind, UnaryOp,
+    Assignment, AstDocument, AstRoot, BinaryOp, Binding, Block, Decl, DeclKind, Expr, ExprKind,
+    Function, InteractiveInput, Name, Parameter, Program, ReturnStatement, Spanned, Stmt, StmtKind,
+    UnaryOp,
 };
 use crate::Span;
 pub trait Visitor {
@@ -83,6 +84,12 @@ pub trait Visitor {
         self.leave_node();
         result
     }
+    fn visit_assignment(&mut self, node: &Assignment) -> Result<(), Self::Error> {
+        self.enter_node(node.span())?;
+        let result = walk_assignment(self, node);
+        self.leave_node();
+        result
+    }
     fn visit_return_statement(&mut self, node: &ReturnStatement) -> Result<(), Self::Error> {
         self.enter_node(node.span())?;
         let result = walk_return_statement(self, node);
@@ -201,6 +208,9 @@ pub fn walk_stmt_kind<V: Visitor + ?Sized>(
         StmtKind::Binding(value) => {
             visitor.visit_binding(value)?;
         }
+        StmtKind::Assignment(value) => {
+            visitor.visit_assignment(value)?;
+        }
         StmtKind::Return(value) => {
             visitor.visit_return_statement(value)?;
         }
@@ -219,6 +229,15 @@ pub fn walk_binding<V: Visitor + ?Sized>(visitor: &mut V, node: &Binding) -> Res
     visitor.visit_span(&node.span)?;
     Ok(())
 }
+pub fn walk_assignment<V: Visitor + ?Sized>(
+    visitor: &mut V,
+    node: &Assignment,
+) -> Result<(), V::Error> {
+    visitor.visit_name(&node.name)?;
+    visitor.visit_expr(&node.value)?;
+    visitor.visit_span(&node.span)?;
+    Ok(())
+}
 pub fn walk_return_statement<V: Visitor + ?Sized>(
     visitor: &mut V,
     node: &ReturnStatement,

crates/frontend/src/grammar.peg

@@ -62,6 +62,7 @@ peg::parser! {
                 Stmt { span: declaration.span, kind: StmtKind::Declaration(declaration) }
             }
             / binding:binding() { binding_statement(binding) }
+            / assignment:assignment() { assignment }
             / expression:expression() {
                 Stmt { span: expression.span, kind: StmtKind::Expression(expression) }
             }
@@ -78,12 +79,22 @@ peg::parser! {
             }
 
         rule block() -> Block
-            = start:lbrace() bindings:binding()* returned:return_statement() end:rbrace() {
-                let mut statements: Vec<Stmt> = bindings.into_iter().map(binding_statement).collect();
+            = start:lbrace() locals:local_statement()* returned:return_statement() end:rbrace() {
+                let mut statements = locals;
                 statements.push(returned);
                 Block { statements, span: start.through(end) }
             }
 
+        rule local_statement() -> Stmt
+            = binding:binding() { binding_statement(binding) }
+            / assignment:assignment() { assignment }
+
+        rule assignment() -> Stmt
+            = name:name() equal() value:expression() {
+                let span = name.span.through(value.span);
+                Stmt { span, kind: StmtKind::Assignment(Assignment { name, value, span }) }
+            }
+
         rule binding() -> Binding
             = start:let_keyword() name:name() equal() value:expression() {
                 Binding { span: start.through(value.span), name, value }

crates/frontend/src/parser.rs

@@ -1,6 +1,6 @@
 use crate::ast::{
-    AstRoot, BinaryOp, Binding, Block, Decl, DeclKind, Expr, ExprKind, Function, InteractiveInput,
-    Name, Parameter, Program, ReturnStatement, Stmt, StmtKind, UnaryOp,
+    Assignment, AstRoot, BinaryOp, Binding, Block, Decl, DeclKind, Expr, ExprKind, Function,
+    InteractiveInput, Name, Parameter, Program, ReturnStatement, Stmt, StmtKind, UnaryOp,
 };
 use crate::lexer::decode_string;
 use crate::{Diagnostic, DiagnosticKind, Span, Token, TokenKind, lex};