Introduce EffectExpr

crates/ra_assists/src/handlers/early_return.rs

@@ -2,7 +2,7 @@ use std::{iter::once, ops::RangeInclusive};
 
 use ra_syntax::{
     algo::replace_children,
-    ast::{self, edit::IndentLevel, make, Block, Pat::TupleStructPat},
+    ast::{self, edit::IndentLevel, make},
     AstNode,
     SyntaxKind::{FN_DEF, LOOP_EXPR, L_CURLY, R_CURLY, WHILE_EXPR, WHITESPACE},
     SyntaxNode,
@@ -47,7 +47,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
     // Check if there is an IfLet that we can handle.
     let if_let_pat = match cond.pat() {
         None => None, // No IfLet, supported.
-        Some(TupleStructPat(pat)) if pat.args().count() == 1 => {
+        Some(ast::Pat::TupleStructPat(pat)) if pat.args().count() == 1 => {
             let path = pat.path()?;
             match path.qualifier() {
                 None => {
@@ -61,9 +61,9 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
     };
 
     let cond_expr = cond.expr()?;
-    let then_block = if_expr.then_branch()?.block()?;
+    let then_block = if_expr.then_branch()?;
 
-    let parent_block = if_expr.syntax().parent()?.ancestors().find_map(ast::Block::cast)?;
+    let parent_block = if_expr.syntax().parent()?.ancestors().find_map(ast::BlockExpr::cast)?;
 
     if parent_block.expr()? != if_expr.clone().into() {
         return None;
@@ -80,7 +80,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
         return None;
     }
 
-    let parent_container = parent_block.syntax().parent()?.parent()?;
+    let parent_container = parent_block.syntax().parent()?;
 
     let early_expression: ast::Expr = match parent_container.kind() {
         WHILE_EXPR | LOOP_EXPR => make::expr_continue(),
@@ -144,13 +144,13 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
             }
         };
         edit.target(if_expr.syntax().text_range());
-        edit.replace_ast(parent_block, ast::Block::cast(new_block).unwrap());
+        edit.replace_ast(parent_block, ast::BlockExpr::cast(new_block).unwrap());
         edit.set_cursor(cursor_position);
 
         fn replace(
             new_expr: &SyntaxNode,
-            then_block: &Block,
+            then_block: &ast::BlockExpr,
-            parent_block: &Block,
+            parent_block: &ast::BlockExpr,
             if_expr: &ast::IfExpr,
         ) -> SyntaxNode {
             let then_block_items = IndentLevel::from(1).decrease_indent(then_block.clone());

crates/ra_assists/src/handlers/inline_local_variable.rs

@@ -89,6 +89,7 @@ pub(crate) fn inline_local_variable(ctx: AssistCtx) -> Option<Assist> {
             | (ast::Expr::ParenExpr(_), _)
             | (ast::Expr::PathExpr(_), _)
             | (ast::Expr::BlockExpr(_), _)
+            | (ast::Expr::EffectExpr(_), _)
             | (_, ast::Expr::CallExpr(_))
             | (_, ast::Expr::TupleExpr(_))
             | (_, ast::Expr::ArrayExpr(_))

crates/ra_assists/src/handlers/introduce_variable.rs

@@ -111,7 +111,7 @@ fn valid_target_expr(node: SyntaxNode) -> Option<ast::Expr> {
 /// expression like a lambda or match arm.
 fn anchor_stmt(expr: ast::Expr) -> Option<(SyntaxNode, bool)> {
     expr.syntax().ancestors().find_map(|node| {
-        if let Some(expr) = node.parent().and_then(ast::Block::cast).and_then(|it| it.expr()) {
+        if let Some(expr) = node.parent().and_then(ast::BlockExpr::cast).and_then(|it| it.expr()) {
             if expr.syntax() == &node {
                 tested_by!(test_introduce_var_last_expr);
                 return Some((node, false));

crates/ra_assists/src/handlers/move_guard.rs

@@ -113,9 +113,9 @@ pub(crate) fn move_arm_cond_to_match_guard(ctx: AssistCtx) -> Option<Assist> {
         "Move condition to match guard",
         |edit| {
             edit.target(if_expr.syntax().text_range());
-            let then_only_expr = then_block.block().and_then(|it| it.statements().next()).is_none();
+            let then_only_expr = then_block.statements().next().is_none();
 
-            match &then_block.block().and_then(|it| it.expr()) {
+            match &then_block.expr() {
                 Some(then_expr) if then_only_expr => {
                     edit.replace(if_expr.syntax().text_range(), then_expr.syntax().text())
                 }

crates/ra_fmt/src/lib.rs

@@ -42,7 +42,6 @@ pub fn unwrap_trivial_block(block: ast::BlockExpr) -> ast::Expr {
 }
 
 pub fn extract_trivial_expression(block: &ast::BlockExpr) -> Option<ast::Expr> {
-    let block = block.block()?;
     let has_anything_else = |thing: &SyntaxNode| -> bool {
         let mut non_trivial_children =
             block.syntax().children_with_tokens().filter(|it| match it.kind() {

crates/ra_hir_def/src/body/lower.rs

@@ -203,10 +203,16 @@ impl ExprCollector<'_> {
 
                 self.alloc_expr(Expr::If { condition, then_branch, else_branch }, syntax_ptr)
             }
-            ast::Expr::TryBlockExpr(e) => {
+            ast::Expr::EffectExpr(e) => match e.effect() {
-                let body = self.collect_block_opt(e.body());
+                ast::Effect::Try(_) => {
+                    let body = self.collect_block_opt(e.block_expr());
                     self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
                 }
+                // FIXME: we need to record these effects somewhere...
+                ast::Effect::Async(_) | ast::Effect::Label(_) | ast::Effect::Unsafe(_) => {
+                    self.collect_block_opt(e.block_expr())
+                }
+            },
             ast::Expr::BlockExpr(e) => self.collect_block(e),
             ast::Expr::LoopExpr(e) => {
                 let body = self.collect_block_opt(e.loop_body());
@@ -494,12 +500,8 @@ impl ExprCollector<'_> {
         }
     }
 
-    fn collect_block(&mut self, expr: ast::BlockExpr) -> ExprId {
+    fn collect_block(&mut self, block: ast::BlockExpr) -> ExprId {
-        let syntax_node_ptr = AstPtr::new(&expr.clone().into());
+        let syntax_node_ptr = AstPtr::new(&block.clone().into());
-        let block = match expr.block() {
-            Some(block) => block,
-            None => return self.alloc_expr(Expr::Missing, syntax_node_ptr),
-        };
         self.collect_block_items(&block);
         let statements = block
             .statements()
@@ -517,7 +519,7 @@ impl ExprCollector<'_> {
         self.alloc_expr(Expr::Block { statements, tail }, syntax_node_ptr)
     }
 
-    fn collect_block_items(&mut self, block: &ast::Block) {
+    fn collect_block_items(&mut self, block: &ast::BlockExpr) {
         let container = ContainerId::DefWithBodyId(self.def);
         for item in block.items() {
             let (def, name): (ModuleDefId, Option<ast::Name>) = match item {

crates/ra_hir_expand/src/db.rs

@@ -330,7 +330,7 @@ fn to_fragment_kind(db: &dyn AstDatabase, id: MacroCallId) -> FragmentKind {
             FragmentKind::Expr
         }
         // FIXME: Expand to statements in appropriate positions; HIR lowering needs to handle that
-        EXPR_STMT | BLOCK => FragmentKind::Expr,
+        EXPR_STMT | BLOCK_EXPR => FragmentKind::Expr,
         ARG_LIST => FragmentKind::Expr,
         TRY_EXPR => FragmentKind::Expr,
         TUPLE_EXPR => FragmentKind::Expr,
@@ -342,7 +342,6 @@ fn to_fragment_kind(db: &dyn AstDatabase, id: MacroCallId) -> FragmentKind {
         CONDITION => FragmentKind::Expr,
         BREAK_EXPR => FragmentKind::Expr,
         RETURN_EXPR => FragmentKind::Expr,
-        BLOCK_EXPR => FragmentKind::Expr,
         MATCH_EXPR => FragmentKind::Expr,
         MATCH_ARM => FragmentKind::Expr,
         MATCH_GUARD => FragmentKind::Expr,

crates/ra_ide/src/completion/completion_context.rs

@@ -344,7 +344,7 @@ impl<'a> CompletionContext<'a> {
                                 stmt.syntax().text_range() == name_ref.syntax().text_range(),
                             );
                         }
-                        if let Some(block) = ast::Block::cast(node) {
+                        if let Some(block) = ast::BlockExpr::cast(node) {
                             return Some(
                                 block.expr().map(|e| e.syntax().text_range())
                                     == Some(name_ref.syntax().text_range()),

crates/ra_ide/src/folding_ranges.rs

@@ -88,7 +88,7 @@ fn fold_kind(kind: SyntaxKind) -> Option<FoldKind> {
         | ITEM_LIST
         | EXTERN_ITEM_LIST
         | USE_TREE_LIST
-        | BLOCK
+        | BLOCK_EXPR
         | MATCH_ARM_LIST
         | ENUM_VARIANT_LIST
         | TOKEN_TREE => Some(FoldKind::Block),

crates/ra_ide/src/join_lines.rs

@@ -129,8 +129,7 @@ fn has_comma_after(node: &SyntaxNode) -> bool {
 }
 
 fn join_single_expr_block(edit: &mut TextEditBuilder, token: &SyntaxToken) -> Option<()> {
-    let block = ast::Block::cast(token.parent())?;
+    let block_expr = ast::BlockExpr::cast(token.parent())?;
-    let block_expr = ast::BlockExpr::cast(block.syntax().parent()?)?;
     if !block_expr.is_standalone() {
         return None;
     }

crates/ra_ide/src/syntax_tree.rs

@@ -120,7 +120,6 @@ SOURCE_FILE@0..11
       R_PAREN@7..8 ")"
     WHITESPACE@8..9 " "
     BLOCK_EXPR@9..11
-      BLOCK@9..11
       L_CURLY@9..10 "{"
       R_CURLY@10..11 "}"
 "#
@@ -153,7 +152,6 @@ SOURCE_FILE@0..60
       R_PAREN@8..9 ")"
     WHITESPACE@9..10 " "
     BLOCK_EXPR@10..60
-      BLOCK@10..60
       L_CURLY@10..11 "{"
       WHITESPACE@11..16 "\n    "
       EXPR_STMT@16..58
@@ -196,7 +194,6 @@ FN_DEF@0..11
     R_PAREN@7..8 ")"
   WHITESPACE@8..9 " "
   BLOCK_EXPR@9..11
-    BLOCK@9..11
     L_CURLY@9..10 "{"
     R_CURLY@10..11 "}"
 "#
@@ -265,7 +262,6 @@ SOURCE_FILE@0..12
       R_PAREN@7..8 ")"
     WHITESPACE@8..9 " "
     BLOCK_EXPR@9..12
-      BLOCK@9..12
       L_CURLY@9..10 "{"
       WHITESPACE@10..11 "\n"
       R_CURLY@11..12 "}"
@@ -300,7 +296,6 @@ SOURCE_FILE@0..12
       R_PAREN@7..8 ")"
     WHITESPACE@8..9 " "
     BLOCK_EXPR@9..12
-      BLOCK@9..12
       L_CURLY@9..10 "{"
       WHITESPACE@10..11 "\n"
       R_CURLY@11..12 "}"
@@ -334,7 +329,6 @@ SOURCE_FILE@0..25
       R_PAREN@7..8 ")"
     WHITESPACE@8..9 " "
     BLOCK_EXPR@9..12
-      BLOCK@9..12
       L_CURLY@9..10 "{"
       WHITESPACE@10..11 "\n"
       R_CURLY@11..12 "}"
@@ -349,7 +343,6 @@ SOURCE_FILE@0..25
       R_PAREN@20..21 ")"
     WHITESPACE@21..22 " "
     BLOCK_EXPR@22..25
-      BLOCK@22..25
       L_CURLY@22..23 "{"
       WHITESPACE@23..24 "\n"
       R_CURLY@24..25 "}"

crates/ra_mbe/src/tests.rs

@@ -266,7 +266,6 @@ fn test_expr_order() {
       L_PAREN@5..6 "("
       R_PAREN@6..7 ")"
     BLOCK_EXPR@7..15
-      BLOCK@7..15
       L_CURLY@7..8 "{"
       EXPR_STMT@8..14
         BIN_EXPR@8..13
@@ -1114,7 +1113,6 @@ fn test_vec() {
     assert_eq!(
         format!("{:#?}", tree).trim(),
         r#"BLOCK_EXPR@0..45
-  BLOCK@0..45
   L_CURLY@0..1 "{"
   LET_STMT@1..20
     LET_KW@1..4 "let"

crates/ra_parser/src/grammar.rs

@@ -143,7 +143,7 @@ pub(crate) fn reparser(
     parent: Option<SyntaxKind>,
 ) -> Option<fn(&mut Parser)> {
     let res = match node {
-        BLOCK => expressions::naked_block,
+        BLOCK_EXPR => expressions::block,
         RECORD_FIELD_DEF_LIST => items::record_field_def_list,
         RECORD_FIELD_LIST => items::record_field_list,
         ENUM_VARIANT_LIST => items::enum_variant_list,

crates/ra_parser/src/grammar/expressions.rs

@@ -59,16 +59,7 @@ pub(crate) fn block(p: &mut Parser) {
         p.error("expected a block");
         return;
     }
-    atom::block_expr(p, None);
+    atom::block_expr(p);
-}
-
-pub(crate) fn naked_block(p: &mut Parser) {
-    assert!(p.at(T!['{']));
-    let m = p.start();
-    p.bump(T!['{']);
-    expr_block_contents(p);
-    p.expect(T!['}']);
-    m.complete(p, BLOCK);
 }
 
 fn is_expr_stmt_attr_allowed(kind: SyntaxKind) -> bool {
@@ -197,7 +188,7 @@ pub(super) fn stmt(p: &mut Parser, with_semi: StmtWithSemi) {
     }
 }
 
-pub(crate) fn expr_block_contents(p: &mut Parser) {
+pub(super) fn expr_block_contents(p: &mut Parser) {
     // This is checked by a validator
     attributes::inner_attributes(p);
 

crates/ra_parser/src/grammar/expressions/atom.rs

@@ -92,7 +92,10 @@ pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<(CompletedMar
                 T![loop] => loop_expr(p, Some(m)),
                 T![for] => for_expr(p, Some(m)),
                 T![while] => while_expr(p, Some(m)),
-                T!['{'] => block_expr(p, Some(m)),
+                T!['{'] => {
+                    block_expr(p);
+                    m.complete(p, EFFECT_EXPR)
+                }
                 _ => {
                     // test_err misplaced_label_err
                     // fn main() {
@@ -108,13 +111,15 @@ pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<(CompletedMar
             let m = p.start();
             p.bump(T![async]);
             p.eat(T![move]);
-            block_expr(p, Some(m))
+            block_expr(p);
+            m.complete(p, EFFECT_EXPR)
         }
         T![match] => match_expr(p),
         T![unsafe] if la == T!['{'] => {
             let m = p.start();
             p.bump(T![unsafe]);
-            block_expr(p, Some(m))
+            block_expr(p);
+            m.complete(p, EFFECT_EXPR)
         }
         T!['{'] => {
             // test for_range_from
@@ -123,7 +128,7 @@ pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<(CompletedMar
             //        break;
             //    }
             // }
-            block_expr(p, None)
+            block_expr(p)
         }
         T![return] => return_expr(p),
         T![continue] => continue_expr(p),
@@ -134,7 +139,7 @@ pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option<(CompletedMar
         }
     };
     let blocklike = match done.kind() {
-        IF_EXPR | WHILE_EXPR | FOR_EXPR | LOOP_EXPR | MATCH_EXPR | BLOCK_EXPR | TRY_BLOCK_EXPR => {
+        IF_EXPR | WHILE_EXPR | FOR_EXPR | LOOP_EXPR | MATCH_EXPR | BLOCK_EXPR | EFFECT_EXPR => {
             BlockLike::Block
         }
         _ => BlockLike::NotBlock,
@@ -234,7 +239,7 @@ fn lambda_expr(p: &mut Parser) -> CompletedMarker {
         if p.at(T!['{']) {
             // test lambda_ret_block
             // fn main() { || -> i32 { 92 }(); }
-            block_expr(p, None);
+            block_expr(p);
         } else {
             p.error("expected `{`");
         }
@@ -464,10 +469,12 @@ fn match_guard(p: &mut Parser) -> CompletedMarker {
 //     unsafe {};
 //     'label: {};
 // }
-pub(super) fn block_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker {
+pub(super) fn block_expr(p: &mut Parser) -> CompletedMarker {
     assert!(p.at(T!['{']));
-    let m = m.unwrap_or_else(|| p.start());
+    let m = p.start();
-    naked_block(p);
+    p.bump(T!['{']);
+    expr_block_contents(p);
+    p.expect(T!['}']);
     m.complete(p, BLOCK_EXPR)
 }
 
@@ -552,8 +559,8 @@ fn try_block_expr(p: &mut Parser, m: Option<Marker>) -> CompletedMarker {
     }
 
     p.bump(T![try]);
-    block(p);
+    block_expr(p);
-    m.complete(p, TRY_EXPR)
+    m.complete(p, EFFECT_EXPR)
 }
 
 // test box_expr

crates/ra_parser/src/syntax_kind/generated.rs

@@ -191,7 +191,7 @@ pub enum SyntaxKind {
     RECORD_LIT,
     RECORD_FIELD_LIST,
     RECORD_FIELD,
-    TRY_BLOCK_EXPR,
+    EFFECT_EXPR,
     BOX_EXPR,
     CALL_EXPR,
     INDEX_EXPR,
@@ -204,7 +204,6 @@ pub enum SyntaxKind {
     PREFIX_EXPR,
     RANGE_EXPR,
     BIN_EXPR,
-    BLOCK,
     EXTERN_BLOCK,
     EXTERN_ITEM_LIST,
     ENUM_VARIANT,

crates/ra_syntax/src/ast.rs

@@ -16,7 +16,7 @@ use crate::{
 };
 
 pub use self::{
-    expr_extensions::{ArrayExprKind, BinOp, ElseBranch, LiteralKind, PrefixOp, RangeOp},
+    expr_extensions::{ArrayExprKind, BinOp, Effect, ElseBranch, LiteralKind, PrefixOp, RangeOp},
     extensions::{
         AttrKind, FieldKind, NameOrNameRef, PathSegmentKind, SelfParamKind, SlicePatComponents,
         StructKind, TypeBoundKind, VisibilityKind,

crates/ra_syntax/src/ast/edit.rs

@@ -28,7 +28,7 @@ impl ast::BinExpr {
 
 impl ast::FnDef {
     #[must_use]
-    pub fn with_body(&self, body: ast::Block) -> ast::FnDef {
+    pub fn with_body(&self, body: ast::BlockExpr) -> ast::FnDef {
         let mut to_insert: ArrayVec<[SyntaxElement; 2]> = ArrayVec::new();
         let old_body_or_semi: SyntaxElement = if let Some(old_body) = self.body() {
             old_body.syntax().clone().into()

crates/ra_syntax/src/ast/expr_extensions.rs

@@ -16,7 +16,7 @@ impl ast::Expr {
             | ast::Expr::WhileExpr(_)
             | ast::Expr::BlockExpr(_)
             | ast::Expr::MatchExpr(_)
-            | ast::Expr::TryBlockExpr(_) => true,
+            | ast::Expr::EffectExpr(_) => true,
             _ => false,
         }
     }
@@ -359,6 +359,33 @@ impl ast::Literal {
     }
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Effect {
+    Async(SyntaxToken),
+    Unsafe(SyntaxToken),
+    Try(SyntaxToken),
+    // Very much not an effect, but we stuff it into this node anyway
+    Label(ast::Label),
+}
+
+impl ast::EffectExpr {
+    pub fn effect(&self) -> Effect {
+        if let Some(token) = self.async_token() {
+            return Effect::Async(token);
+        }
+        if let Some(token) = self.unsafe_token() {
+            return Effect::Unsafe(token);
+        }
+        if let Some(token) = self.try_token() {
+            return Effect::Try(token);
+        }
+        if let Some(label) = self.label() {
+            return Effect::Label(label);
+        }
+        unreachable!("ast::EffectExpr without Effect")
+    }
+}
+
 impl ast::BlockExpr {
     /// false if the block is an intrinsic part of the syntax and can't be
     /// replaced with arbitrary expression.
@@ -368,15 +395,12 @@ impl ast::BlockExpr {
     /// const FOO: () = { stand_alone };
     /// ```
     pub fn is_standalone(&self) -> bool {
-        if self.unsafe_token().is_some() || self.async_token().is_some() {
+        let parent = match self.syntax().parent() {
-            return false;
+            Some(it) => it,
-        }
-        let kind = match self.syntax().parent() {
             None => return true,
-            Some(it) => it.kind(),
         };
-        match kind {
+        match parent.kind() {
-            FN_DEF | IF_EXPR | WHILE_EXPR | LOOP_EXPR | TRY_BLOCK_EXPR => false,
+            FN_DEF | IF_EXPR | WHILE_EXPR | LOOP_EXPR | EFFECT_EXPR => false,
             _ => true,
         }
     }

crates/ra_syntax/src/ast/generated/nodes.rs

@@ -476,13 +476,16 @@ impl LoopExpr {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct TryBlockExpr {
+pub struct EffectExpr {
     pub(crate) syntax: SyntaxNode,
 }
-impl ast::AttrsOwner for TryBlockExpr {}
+impl ast::AttrsOwner for EffectExpr {}
-impl TryBlockExpr {
+impl EffectExpr {
+    pub fn label(&self) -> Option<Label> { support::child(&self.syntax) }
     pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
-    pub fn body(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
+    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn block_expr(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -551,11 +554,12 @@ pub struct BlockExpr {
     pub(crate) syntax: SyntaxNode,
 }
 impl ast::AttrsOwner for BlockExpr {}
+impl ast::ModuleItemOwner for BlockExpr {}
 impl BlockExpr {
-    pub fn label(&self) -> Option<Label> { support::child(&self.syntax) }
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
-    pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn statements(&self) -> AstChildren<Stmt> { support::children(&self.syntax) }
-    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
-    pub fn block(&self) -> Option<Block> { support::child(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -627,8 +631,8 @@ pub struct TryExpr {
 }
 impl ast::AttrsOwner for TryExpr {}
 impl TryExpr {
-    pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
     pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn question_mark_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![?]) }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -1121,19 +1125,6 @@ impl Condition {
     pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct Block {
-    pub(crate) syntax: SyntaxNode,
-}
-impl ast::AttrsOwner for Block {}
-impl ast::ModuleItemOwner for Block {}
-impl Block {
-    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
-    pub fn statements(&self) -> AstChildren<Stmt> { support::children(&self.syntax) }
-    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
-    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
-}
-
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct ParamList {
     pub(crate) syntax: SyntaxNode,
@@ -1477,7 +1468,7 @@ pub enum Expr {
     FieldExpr(FieldExpr),
     AwaitExpr(AwaitExpr),
     TryExpr(TryExpr),
-    TryBlockExpr(TryBlockExpr),
+    EffectExpr(EffectExpr),
     CastExpr(CastExpr),
     RefExpr(RefExpr),
     PrefixExpr(PrefixExpr),
@@ -1960,8 +1951,8 @@ impl AstNode for LoopExpr {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
-impl AstNode for TryBlockExpr {
+impl AstNode for EffectExpr {
-    fn can_cast(kind: SyntaxKind) -> bool { kind == TRY_BLOCK_EXPR }
+    fn can_cast(kind: SyntaxKind) -> bool { kind == EFFECT_EXPR }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
         if Self::can_cast(syntax.kind()) {
             Some(Self { syntax })
@@ -2653,17 +2644,6 @@ impl AstNode for Condition {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
-impl AstNode for Block {
-    fn can_cast(kind: SyntaxKind) -> bool { kind == BLOCK }
-    fn cast(syntax: SyntaxNode) -> Option<Self> {
-        if Self::can_cast(syntax.kind()) {
-            Some(Self { syntax })
-        } else {
-            None
-        }
-    }
-    fn syntax(&self) -> &SyntaxNode { &self.syntax }
-}
 impl AstNode for ParamList {
     fn can_cast(kind: SyntaxKind) -> bool { kind == PARAM_LIST }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -3312,8 +3292,8 @@ impl From<AwaitExpr> for Expr {
 impl From<TryExpr> for Expr {
     fn from(node: TryExpr) -> Expr { Expr::TryExpr(node) }
 }
-impl From<TryBlockExpr> for Expr {
+impl From<EffectExpr> for Expr {
-    fn from(node: TryBlockExpr) -> Expr { Expr::TryBlockExpr(node) }
+    fn from(node: EffectExpr) -> Expr { Expr::EffectExpr(node) }
 }
 impl From<CastExpr> for Expr {
     fn from(node: CastExpr) -> Expr { Expr::CastExpr(node) }
@@ -3345,9 +3325,10 @@ impl AstNode for Expr {
             TUPLE_EXPR | ARRAY_EXPR | PAREN_EXPR | PATH_EXPR | LAMBDA_EXPR | IF_EXPR
             | LOOP_EXPR | FOR_EXPR | WHILE_EXPR | CONTINUE_EXPR | BREAK_EXPR | LABEL
             | BLOCK_EXPR | RETURN_EXPR | MATCH_EXPR | RECORD_LIT | CALL_EXPR | INDEX_EXPR
-            | METHOD_CALL_EXPR | FIELD_EXPR | AWAIT_EXPR | TRY_EXPR | TRY_BLOCK_EXPR
+            | METHOD_CALL_EXPR | FIELD_EXPR | AWAIT_EXPR | TRY_EXPR | EFFECT_EXPR | CAST_EXPR
-            | CAST_EXPR | REF_EXPR | PREFIX_EXPR | RANGE_EXPR | BIN_EXPR | LITERAL | MACRO_CALL
+            | REF_EXPR | PREFIX_EXPR | RANGE_EXPR | BIN_EXPR | LITERAL | MACRO_CALL | BOX_EXPR => {
-            | BOX_EXPR => true,
+                true
+            }
             _ => false,
         }
     }
@@ -3375,7 +3356,7 @@ impl AstNode for Expr {
             FIELD_EXPR => Expr::FieldExpr(FieldExpr { syntax }),
             AWAIT_EXPR => Expr::AwaitExpr(AwaitExpr { syntax }),
             TRY_EXPR => Expr::TryExpr(TryExpr { syntax }),
-            TRY_BLOCK_EXPR => Expr::TryBlockExpr(TryBlockExpr { syntax }),
+            EFFECT_EXPR => Expr::EffectExpr(EffectExpr { syntax }),
             CAST_EXPR => Expr::CastExpr(CastExpr { syntax }),
             REF_EXPR => Expr::RefExpr(RefExpr { syntax }),
             PREFIX_EXPR => Expr::PrefixExpr(PrefixExpr { syntax }),
@@ -3412,7 +3393,7 @@ impl AstNode for Expr {
             Expr::FieldExpr(it) => &it.syntax,
             Expr::AwaitExpr(it) => &it.syntax,
             Expr::TryExpr(it) => &it.syntax,
-            Expr::TryBlockExpr(it) => &it.syntax,
+            Expr::EffectExpr(it) => &it.syntax,
             Expr::CastExpr(it) => &it.syntax,
             Expr::RefExpr(it) => &it.syntax,
             Expr::PrefixExpr(it) => &it.syntax,
@@ -3893,7 +3874,7 @@ impl std::fmt::Display for LoopExpr {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
-impl std::fmt::Display for TryBlockExpr {
+impl std::fmt::Display for EffectExpr {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
     }
@@ -4208,11 +4189,6 @@ impl std::fmt::Display for Condition {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
-impl std::fmt::Display for Block {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        std::fmt::Display::fmt(self.syntax(), f)
-    }
-}
 impl std::fmt::Display for ParamList {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)

crates/ra_syntax/src/ast/make.rs

@@ -82,10 +82,10 @@ pub fn block_expr(
     ast_from_text(&format!("fn f() {}", buf))
 }
 
-pub fn block_from_expr(e: ast::Expr) -> ast::Block {
+pub fn block_from_expr(e: ast::Expr) -> ast::BlockExpr {
     return from_text(&format!("{{ {} }}", e));
 
-    fn from_text(text: &str) -> ast::Block {
+    fn from_text(text: &str) -> ast::BlockExpr {
         ast_from_text(&format!("fn f() {}", text))
     }
 }

crates/ra_syntax/src/lib.rs

@@ -237,8 +237,7 @@ fn api_walkthrough() {
 
     // Let's get the `1 + 1` expression!
     let body: ast::BlockExpr = func.body().unwrap();
-    let block = body.block().unwrap();
+    let expr: ast::Expr = body.expr().unwrap();
-    let expr: ast::Expr = block.expr().unwrap();
 
     // Enums are used to group related ast nodes together, and can be used for
     // matching. However, because there are no public fields, it's possible to
@@ -274,8 +273,8 @@ fn api_walkthrough() {
     assert_eq!(text.to_string(), "1 + 1");
 
     // There's a bunch of traversal methods on `SyntaxNode`:
-    assert_eq!(expr_syntax.parent().as_ref(), Some(block.syntax()));
+    assert_eq!(expr_syntax.parent().as_ref(), Some(body.syntax()));
-    assert_eq!(block.syntax().first_child_or_token().map(|it| it.kind()), Some(T!['{']));
+    assert_eq!(body.syntax().first_child_or_token().map(|it| it.kind()), Some(T!['{']));
     assert_eq!(
         expr_syntax.next_sibling_or_token().map(|it| it.kind()),
         Some(SyntaxKind::WHITESPACE)

crates/ra_syntax/src/validation/block.rs

@@ -6,19 +6,17 @@ use crate::{
     SyntaxKind::*,
 };
 
-pub(crate) fn validate_block_expr(expr: ast::BlockExpr, errors: &mut Vec<SyntaxError>) {
+pub(crate) fn validate_block_expr(block: ast::BlockExpr, errors: &mut Vec<SyntaxError>) {
-    if let Some(parent) = expr.syntax().parent() {
+    if let Some(parent) = block.syntax().parent() {
         match parent.kind() {
-            FN_DEF | EXPR_STMT | BLOCK => return,
+            FN_DEF | EXPR_STMT | BLOCK_EXPR => return,
             _ => {}
         }
     }
-    if let Some(block) = expr.block() {
     errors.extend(block.attrs().map(|attr| {
         SyntaxError::new(
             "A block in this position cannot accept inner attributes",
             attr.syntax().text_range(),
         )
     }))
-    }
 }

xtask/src/ast_src.rs

@@ -162,7 +162,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "RECORD_LIT",
         "RECORD_FIELD_LIST",
         "RECORD_FIELD",
-        "TRY_BLOCK_EXPR",
+        "EFFECT_EXPR",
         "BOX_EXPR",
         // postfix
         "CALL_EXPR",
@@ -177,7 +177,6 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "PREFIX_EXPR",
         "RANGE_EXPR", // just weird
         "BIN_EXPR",
-        "BLOCK",
         "EXTERN_BLOCK",
         "EXTERN_ITEM_LIST",
         "ENUM_VARIANT",
@@ -440,7 +439,7 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
         }
         struct IfExpr: AttrsOwner { T![if], Condition }
         struct LoopExpr: AttrsOwner, LoopBodyOwner { T![loop] }
-        struct TryBlockExpr: AttrsOwner { T![try], body: BlockExpr }
+        struct EffectExpr: AttrsOwner { Label, T![try], T![unsafe], T![async], BlockExpr }
         struct ForExpr: AttrsOwner, LoopBodyOwner {
             T![for],
             Pat,
@@ -451,7 +450,9 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
         struct ContinueExpr: AttrsOwner { T![continue], T![lifetime] }
         struct BreakExpr: AttrsOwner { T![break], T![lifetime], Expr }
         struct Label { T![lifetime] }
-        struct BlockExpr: AttrsOwner { Label, T![unsafe], T![async], Block  }
+        struct BlockExpr: AttrsOwner, ModuleItemOwner {
+            T!['{'], statements: [Stmt], Expr, T!['}'],
+        }
         struct ReturnExpr: AttrsOwner { Expr }
         struct CallExpr: ArgListOwner { Expr }
         struct MethodCallExpr: AttrsOwner, ArgListOwner {
@@ -460,7 +461,7 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
         struct IndexExpr: AttrsOwner { T!['['], T![']'] }
         struct FieldExpr: AttrsOwner { Expr, T![.], NameRef }
         struct AwaitExpr: AttrsOwner { Expr, T![.], T![await] }
-        struct TryExpr: AttrsOwner { T![try], Expr }
+        struct TryExpr: AttrsOwner { Expr, T![?] }
         struct CastExpr: AttrsOwner { Expr, T![as], TypeRef }
         struct RefExpr: AttrsOwner { T![&], T![raw], T![mut], Expr }
         struct PrefixExpr: AttrsOwner { /*PrefixOp,*/ Expr }
@@ -556,12 +557,6 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
             T![;],
         }
         struct Condition { T![let], Pat, T![=], Expr }
-        struct Block: AttrsOwner, ModuleItemOwner {
-            T!['{'],
-            statements: [Stmt],
-            Expr,
-            T!['}'],
-        }
         struct ParamList {
             T!['('],
             SelfParam,
@@ -722,7 +717,7 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
             FieldExpr,
             AwaitExpr,
             TryExpr,
-            TryBlockExpr,
+            EffectExpr,
             CastExpr,
             RefExpr,
             PrefixExpr,

xtask/src/codegen/gen_syntax.rs

@@ -432,6 +432,7 @@ impl Field<'_> {
                     ":" => "colon",
                     "::" => "coloncolon",
                     "#" => "pound",
+                    "?" => "question_mark",
                     _ => name,
                 };
                 format_ident!("{}_token", name)