adding struct syntax

hblang/examples/structs.hb

@@ -0,0 +1,9 @@
+Ty := struct {
+	a: int
+	b: int
+}
+
+main := fn(): int {
+	inst := Ty.{ a: 1, b: 2 };
+	return inst.a + inst.b;
+}

hblang/src/codegen.rs

@@ -915,5 +915,6 @@ mod tests {
         loops => include_str!("../examples/loops.hb");
         fb_driver => include_str!("../examples/fb_driver.hb");
         pointers => include_str!("../examples/pointers.hb");
+        structs => include_str!("../examples/structs.hb");
     }
 }

hblang/src/lexer.rs

@@ -91,17 +91,20 @@ gen_token_kind! {
         Break    = b"break",
         Continue = b"continue",
         Fn       = b"fn",
+        Struct   = b"struct",
         #[punkt]
-        LParen = b'(',
-        RParen = b')',
-        LBrace = b'{',
-        RBrace = b'}',
-        Semi =   b';',
-        Colon =  b':',
-        Comma =  b',',
+        LParen = "(",
+        RParen = ")",
+        LBrace = "{",
+        RBrace = "}",
+        Semi   = ";",
+        Colon  = ":",
+        Comma  = ",",
+        Dot    = ".",
+        Ctor   = ".{",
         #[ops]
         #[prec = 1]
-        Decl =   ":=",
+        Decl   = ":=",
         Assign = "=",
         #[prec = 21]
         Le = "<=",
@@ -109,10 +112,10 @@ gen_token_kind! {
         #[prec = 22]
         Amp = "&",
         #[prec = 23]
-        Plus =  "+",
+        Plus  = "+",
         Minus = "-",
         #[prec = 24]
-        Star =   "*",
+        Star   = "*",
         FSlash = "/",
     }
 }
@@ -202,6 +205,8 @@ impl<'a> Iterator for Lexer<'a> {
                 b':' if self.advance_if(b'=') => T::Decl,
                 b':' => T::Colon,
                 b',' => T::Comma,
+                b'.' if self.advance_if(b'{') => T::Ctor,
+                b'.' => T::Dot,
                 b';' => T::Semi,
                 b'=' if self.advance_if(b'=') => T::Eq,
                 b'=' => T::Assign,

hblang/src/parser.rs

@@ -139,6 +139,18 @@ impl<'a, 'b> Parser<'a, 'b> {
         let frame = self.idents.len();
         let token = self.next();
         let mut expr = match token.kind {
+            T::Struct => E::Struct {
+                pos:    token.start,
+                fields: {
+                    self.expect_advance(T::LBrace);
+                    self.collect_list(T::Comma, T::RBrace, |s| {
+                        let name = s.expect_advance(T::Ident);
+                        s.expect_advance(T::Colon);
+                        let ty = s.expr();
+                        (s.lexer.slice(name.range()), ty)
+                    })
+                },
+            },
             T::Ident => {
                 let (id, last) = self.resolve_ident(token, self.token.kind == T::Decl);
                 let name = self.lexer.slice(token.range());
@@ -207,14 +219,32 @@ impl<'a, 'b> Parser<'a, 'b> {
         };
 
         loop {
-            expr = match self.token.kind {
-                T::LParen => {
-                    self.next();
-                    Expr::Call {
-                        func: self.arena.alloc(expr),
-                        args: self.collect_list(T::Comma, T::RParen, Self::expr),
-                    }
-                }
+            let token = self.token.kind;
+            if matches!(token, T::LParen | T::Ctor | T::Dot) {
+                self.next();
+            }
+
+            expr = match token {
+                T::LParen => Expr::Call {
+                    func: self.arena.alloc(expr),
+                    args: self.collect_list(T::Comma, T::RParen, Self::expr),
+                },
+                T::Ctor => E::Ctor {
+                    ty:     self.arena.alloc(expr),
+                    fields: self.collect_list(T::Comma, T::RBrace, |s| {
+                        let name = s.expect_advance(T::Ident);
+                        s.expect_advance(T::Colon);
+                        let val = s.expr();
+                        (s.lexer.slice(name.range()), val)
+                    }),
+                },
+                T::Dot => E::Field {
+                    ty:    self.arena.alloc(expr),
+                    field: {
+                        let token = self.expect_advance(T::Ident);
+                        self.lexer.slice(token.range())
+                    },
+                },
                 _ => break,
             }
         }
@@ -313,16 +343,16 @@ pub enum Expr<'a> {
     Closure {
         pos:  u32,
         args: &'a [Arg<'a>],
-        ret:  &'a Expr<'a>,
-        body: &'a Expr<'a>,
+        ret:  &'a Self,
+        body: &'a Self,
     },
     Call {
-        func: &'a Expr<'a>,
-        args: &'a [Expr<'a>],
+        func: &'a Self,
+        args: &'a [Self],
     },
     Return {
         pos: u32,
-        val: Option<&'a Expr<'a>>,
+        val: Option<&'a Self>,
     },
     Ident {
         name: &'a str,
@@ -331,31 +361,43 @@ pub enum Expr<'a> {
     },
     Block {
         pos:   u32,
-        stmts: &'a [Expr<'a>],
+        stmts: &'a [Self],
     },
     Number {
         pos:   u32,
         value: u64,
     },
     BinOp {
-        left:  &'a Expr<'a>,
+        left:  &'a Self,
         op:    TokenKind,
-        right: &'a Expr<'a>,
+        right: &'a Self,
     },
     If {
         pos:   u32,
-        cond:  &'a Expr<'a>,
-        then:  &'a Expr<'a>,
-        else_: Option<&'a Expr<'a>>,
+        cond:  &'a Self,
+        then:  &'a Self,
+        else_: Option<&'a Self>,
     },
     Loop {
         pos:  u32,
-        body: &'a Expr<'a>,
+        body: &'a Self,
     },
     UnOp {
         pos: u32,
         op:  TokenKind,
-        val: &'a Expr<'a>,
+        val: &'a Self,
+    },
+    Struct {
+        pos:    u32,
+        fields: &'a [(&'a str, Self)],
+    },
+    Ctor {
+        ty:     &'a Self,
+        fields: &'a [(&'a str, Self)],
+    },
+    Field {
+        ty:    &'a Self,
+        field: &'a str,
     },
 }
 
@@ -366,6 +408,29 @@ impl<'a> std::fmt::Display for Expr<'a> {
         }
 
         match *self {
+            Self::Field { ty, field } => write!(f, "{}.{}", ty, field),
+            Self::Struct { fields, .. } => {
+                write!(f, "struct {{")?;
+                let first = &mut true;
+                for (name, ty) in fields {
+                    if !std::mem::take(first) {
+                        write!(f, ", ")?;
+                    }
+                    write!(f, "{}: {}", name, ty)?;
+                }
+                write!(f, "}}")
+            }
+            Self::Ctor { ty, fields } => {
+                write!(f, "{} {{", ty)?;
+                let first = &mut true;
+                for (name, val) in fields {
+                    if !std::mem::take(first) {
+                        write!(f, ", ")?;
+                    }
+                    write!(f, "{}: {}", name, val)?;
+                }
+                write!(f, "}}")
+            }
             Self::UnOp { op, val, .. } => write!(f, "{}{}", op, val),
             Self::Break { .. } => write!(f, "break;"),
             Self::Continue { .. } => write!(f, "continue;"),