Allow macro_rules! to also define item and stmt macros

doc/rust.md

@@ -494,7 +494,7 @@ transcriber : '(' transcriber * ')' | '[' transcriber * ']'
 
 User-defined syntax extensions are called "macros", and they can be defined
 with the `macro_rules!` syntax extension. User-defined macros can currently
-only be invoked in expression position.
+be invoked as expressions, statements, or items.
 
 (A `sep_token` is any token other than `*` and `+`. A `non_special_token` is
 any token other than a delimiter or `$`.)
@@ -510,7 +510,7 @@ For parsing reasons, delimiters must be balanced, but they are otherwise not spe
 
 In the matcher, `$` _name_ `:` _designator_ matches the nonterminal in the
 Rust syntax named by _designator_. Valid designators are `item`, `block`,
-`stmt`, `pat`, `expr`, `ty` (type), `ident`, `path`, `matchers` (lhs of the `=>` in macro rules), 
+`stmt`, `pat`, `expr`, `ty` (type), `ident`, `path`, `matchers` (lhs of the `=>` in macro rules),
 `tt` (rhs of the `=>` in macro rules). In the transcriber, the designator is already known, and so only
 the name of a matched nonterminal comes after the dollar sign.
 
@@ -2196,7 +2196,7 @@ Records and structures can also be pattern-matched and their fields bound to var
 When matching fields of a record,
 the fields being matched are specified first,
 then a placeholder (`_`) represents the remaining fields.
- 
+
 ~~~~
 # type options = {choose: bool, size: ~str};
 # type player = {player: ~str, stats: (), options: options};
@@ -2726,7 +2726,7 @@ The kinds are:
     structural types containing only other sendable types.
 `Owned`
   : Types of this kind do not contain any borrowed pointers;
-    this can be a useful guarantee for code that breaks borrowing assumptions using [`unsafe` operations](#unsafe-functions).    
+    this can be a useful guarantee for code that breaks borrowing assumptions using [`unsafe` operations](#unsafe-functions).
 `Copy`
   : This kind includes all types that can be copied. All types with
     sendable kind are copyable, as are managed boxes, managed closures,

src/libcore/hash.rs

@@ -203,14 +203,14 @@ impl &SipState : io::Writer {
 
         macro_rules! compress (
             ($v0:expr, $v1:expr, $v2:expr, $v3:expr) =>
-            {
+            ({
                 $v0 += $v1; $v1 = rotl!($v1, 13); $v1 ^= $v0;
                 $v0 = rotl!($v0, 32);
                 $v2 += $v3; $v3 = rotl!($v3, 16); $v3 ^= $v2;
                 $v0 += $v3; $v3 = rotl!($v3, 21); $v3 ^= $v0;
                 $v2 += $v1; $v1 = rotl!($v1, 17); $v1 ^= $v2;
                 $v2 = rotl!($v2, 32);
-            }
+            })
         );
 
         let length = msg.len();

src/libcore/pipes.rs

@@ -86,7 +86,7 @@ use option::unwrap;
 const SPIN_COUNT: uint = 0;
 
 macro_rules! move_it (
-    { $x:expr } => { unsafe { let y = move *ptr::addr_of(&($x)); move y } }
+    { $x:expr } => ( unsafe { let y = move *ptr::addr_of(&($x)); move y } )
 )
 
 #[doc(hidden)]

src/libcore/task/spawn.rs

@@ -67,7 +67,7 @@ use rt::rust_task;
 use rt::rust_closure;
 
 macro_rules! move_it (
-    { $x:expr } => { unsafe { let y = move *ptr::addr_of(&($x)); move y } }
+    { $x:expr } => ( unsafe { let y = move *ptr::addr_of(&($x)); move y } )
 )
 
 type TaskSet = send_map::linear::LinearMap<*rust_task,()>;

src/librustc/middle/astencode.rs

@@ -239,7 +239,8 @@ fn simplify_ast(ii: ast::inlined_item) -> ast::inlined_item {
             match stmt.node {
               ast::stmt_expr(_, _) | ast::stmt_semi(_, _) |
               ast::stmt_decl(@{node: ast::decl_local(_), span: _}, _) => true,
-              ast::stmt_decl(@{node: ast::decl_item(_), span: _}, _) => false
+              ast::stmt_decl(@{node: ast::decl_item(_), span: _}, _) => false,
+              ast::stmt_mac(*) => fail ~"unexpanded macro in astencode"
             }
         };
         let blk_sans_items = { stmts: stmts_sans_items,.. blk };

src/librustc/middle/liveness.rs

@@ -1031,6 +1031,10 @@ impl Liveness {
           stmt_expr(expr, _) | stmt_semi(expr, _) => {
             return self.propagate_through_expr(expr, succ);
           }
+
+          stmt_mac(*) => {
+            self.tcx.sess.span_bug(stmt.span, ~"unexpanded macro");
+          }
         }
     }
 

src/librustc/middle/region.rs

@@ -245,6 +245,7 @@ fn resolve_stmt(stmt: @ast::stmt, cx: ctxt, visitor: visit::vt<ctxt>) {
         expr_cx.parent = Some(stmt_id);
         visit::visit_stmt(stmt, expr_cx, visitor);
       }
+      ast::stmt_mac(*) => cx.sess.bug(~"unexpanded macro")
     }
 }
 

src/librustc/middle/trans/alt.rs

@@ -831,14 +831,14 @@ fn root_pats_as_necessary(bcx: block, m: &[@Match],
 // matches should fit that sort of pattern or NONE (however, some of the
 // matches may be wildcards like _ or identifiers).
 macro_rules! any_pat (
-    ($m:expr, $pattern:pat) => {
+    ($m:expr, $pattern:pat) => (
         vec::any($m, |br| {
             match br.pats[col].node {
                 $pattern => true,
                 _ => false
             }
         })
-    }
+    )
 )
 
 fn any_box_pat(m: &[@Match], col: uint) -> bool {

src/librustc/middle/trans/base.rs

@@ -1026,6 +1026,7 @@ fn trans_stmt(cx: block, s: ast::stmt) -> block {
                 ast::decl_item(i) => trans_item(cx.fcx.ccx, *i)
             }
         }
+        ast::stmt_mac(*) => cx.tcx().sess.bug(~"unexpanded macro")
     }
 
     return bcx;

src/librustc/middle/ty.rs

@@ -3181,6 +3181,7 @@ fn stmt_node_id(s: @ast::stmt) -> ast::node_id {
       ast::stmt_decl(_, id) | stmt_expr(_, id) | stmt_semi(_, id) => {
         return id;
       }
+      ast::stmt_mac(*) => fail ~"unexpanded macro in trans"
     }
 }
 

src/librustc/middle/typeck/check.rs

@@ -2362,6 +2362,7 @@ fn check_stmt(fcx: @fn_ctxt, stmt: @ast::stmt) -> bool {
         node_id = id;
         bot = check_expr(fcx, expr, None);
       }
+      ast::stmt_mac(*) => fcx.ccx.tcx.sess.bug(~"unexpanded macro")
     }
     fcx.write_nil(node_id);
     return bot;

src/librusti/rusti.rs

@@ -52,7 +52,7 @@ fn record(repl: Repl, blk: @ast::blk, intr: @token::ident_interner) -> Repl {
         let new_stmts = do with_pp(intr) |pp, writer| {
             for blk.node.stmts.each |stmt| {
                 match stmt.node {
-                    ast::stmt_decl(*) => {
+                    ast::stmt_decl(*) | ast::stmt_mac(*) => {
                         pprust::print_stmt(pp, **stmt);
                         writer.write_line(~"");
                     }

src/libsyntax/ast.rs

@@ -896,6 +896,9 @@ enum stmt_ {
 
     // expr with trailing semi-colon (may have any type):
     stmt_semi(@expr, node_id),
+
+    // bool: is there a trailing sem-colon?
+    stmt_mac(mac, bool),
 }
 
 // FIXME (pending discussion of #1697, #2178...): local should really be

src/libsyntax/ast_util.rs

@@ -39,7 +39,8 @@ pure fn stmt_id(s: stmt) -> node_id {
     match s.node {
       stmt_decl(_, id) => id,
       stmt_expr(_, id) => id,
-      stmt_semi(_, id) => id
+      stmt_semi(_, id) => id,
+      stmt_mac(*) => fail ~"attempted to analyze unexpanded stmt",
     }
 }
 

src/libsyntax/ext/base.rs

@@ -12,7 +12,7 @@ use ast_util::dummy_sp;
 // new-style macro! tt code:
 //
 //    syntax_expander_tt, syntax_expander_tt_item, mac_result,
-//    expr_tt, item_tt
+//    normal_tt, item_tt
 //
 // also note that ast::mac has way too many cases and can probably
 // be trimmed down substantially.
@@ -44,6 +44,7 @@ type syntax_expander_tt_item_
 enum mac_result {
     mr_expr(@ast::expr),
     mr_item(@ast::item),
+    mr_any(fn@()-> @ast::expr, fn@()-> Option<@ast::item>, fn@()->@ast::stmt),
     mr_def(macro_def)
 }
 
@@ -59,7 +60,10 @@ enum syntax_extension {
     item_decorator(item_decorator),
 
     // Token-tree expanders
-    expr_tt(syntax_expander_tt),
+    normal_tt(syntax_expander_tt),
+
+    // perhaps macro_rules! will lose its odd special identifier argument,
+    // and this can go away also
     item_tt(syntax_expander_tt_item),
 }
 
@@ -68,8 +72,8 @@ enum syntax_extension {
 fn syntax_expander_table() -> HashMap<~str, syntax_extension> {
     fn builtin(f: syntax_expander_) -> syntax_extension
         {normal({expander: f, span: None})}
-    fn builtin_expr_tt(f: syntax_expander_tt_) -> syntax_extension {
-        expr_tt({expander: f, span: None})
+    fn builtin_normal_tt(f: syntax_expander_tt_) -> syntax_extension {
+        normal_tt({expander: f, span: None})
     }
     fn builtin_item_tt(f: syntax_expander_tt_item_) -> syntax_extension {
         item_tt({expander: f, span: None})
@@ -93,7 +97,7 @@ fn syntax_expander_table() -> HashMap<~str, syntax_extension> {
     syntax_expanders.insert(~"ident_to_str",
                             builtin(ext::ident_to_str::expand_syntax_ext));
     syntax_expanders.insert(~"log_syntax",
-                            builtin_expr_tt(
+                            builtin_normal_tt(
                                 ext::log_syntax::expand_syntax_ext));
     syntax_expanders.insert(~"ast",
                             builtin(ext::qquote::expand_ast));
@@ -105,18 +109,18 @@ fn syntax_expander_table() -> HashMap<~str, syntax_extension> {
                                 ext::deriving::expand_deriving_iter_bytes));
 
     // Quasi-quoting expanders
-    syntax_expanders.insert(~"quote_tokens",
-                            builtin_expr_tt(ext::quote::expand_quote_tokens));
+    syntax_expanders.insert(
+        ~"quote_tokens", builtin_normal_tt(ext::quote::expand_quote_tokens));
     syntax_expanders.insert(~"quote_expr",
-                            builtin_expr_tt(ext::quote::expand_quote_expr));
+                            builtin_normal_tt(ext::quote::expand_quote_expr));
     syntax_expanders.insert(~"quote_type",
-                            builtin_expr_tt(ext::quote::expand_quote_type));
+                            builtin_normal_tt(ext::quote::expand_quote_type));
     syntax_expanders.insert(~"quote_item",
-                            builtin_expr_tt(ext::quote::expand_quote_item));
+                            builtin_normal_tt(ext::quote::expand_quote_item));
     syntax_expanders.insert(~"quote_pat",
-                            builtin_expr_tt(ext::quote::expand_quote_pat));
+                            builtin_normal_tt(ext::quote::expand_quote_pat));
     syntax_expanders.insert(~"quote_stmt",
-                            builtin_expr_tt(ext::quote::expand_quote_stmt));
+                            builtin_normal_tt(ext::quote::expand_quote_stmt));
 
     syntax_expanders.insert(~"line",
                             builtin(ext::source_util::expand_line));
@@ -138,7 +142,7 @@ fn syntax_expander_table() -> HashMap<~str, syntax_extension> {
                             builtin_item_tt(ext::pipes::expand_proto));
     syntax_expanders.insert(
         ~"trace_macros",
-        builtin_expr_tt(ext::trace_macros::expand_trace_macros));
+        builtin_normal_tt(ext::trace_macros::expand_trace_macros));
     return syntax_expanders;
 }