visit::Visitor refactor: replace (&mut BorrowckVisitor, @BorrowckCtxt) with &mut BorrowckCtxt.

src/librustc/middle/borrowck/check_loans.rs

@@ -33,7 +33,7 @@ use util::ppaux::Repr;
 
 #[deriving(Clone)]
 struct CheckLoanCtxt<'self> {
-    bccx: @BorrowckCtxt,
+    bccx: &'self BorrowckCtxt,
     dfcx_loans: &'self LoanDataFlow,
     move_data: @move_data::FlowedMoveData,
     all_loans: &'self [Loan],
@@ -60,7 +60,7 @@ impl<'self> Visitor<()> for CheckLoanCtxt<'self> {
     }
 }
 
-pub fn check_loans(bccx: @BorrowckCtxt,
+pub fn check_loans(bccx: &BorrowckCtxt,
                    dfcx_loans: &LoanDataFlow,
                    move_data: move_data::FlowedMoveData,
                    all_loans: &[Loan],

src/librustc/middle/borrowck/gather_loans/gather_moves.rs

@@ -22,7 +22,7 @@ use syntax::ast_util;
 use syntax::codemap::Span;
 use util::ppaux::{UserString};
 
-pub fn gather_decl(bccx: @BorrowckCtxt,
+pub fn gather_decl(bccx: &BorrowckCtxt,
                    move_data: &mut MoveData,
                    decl_id: ast::NodeId,
                    _decl_span: Span,
@@ -31,7 +31,7 @@ pub fn gather_decl(bccx: @BorrowckCtxt,
     move_data.add_move(bccx.tcx, loan_path, decl_id, Declared);
 }
 
-pub fn gather_move_from_expr(bccx: @BorrowckCtxt,
+pub fn gather_move_from_expr(bccx: &BorrowckCtxt,
                              move_data: &mut MoveData,
                              move_expr: @ast::Expr,
                              cmt: mc::cmt) {
@@ -39,7 +39,7 @@ pub fn gather_move_from_expr(bccx: @BorrowckCtxt,
                                  MoveExpr(move_expr), cmt);
 }
 
-pub fn gather_move_from_pat(bccx: @BorrowckCtxt,
+pub fn gather_move_from_pat(bccx: &BorrowckCtxt,
                             move_data: &mut MoveData,
                             move_pat: @ast::Pat,
                             cmt: mc::cmt) {
@@ -47,7 +47,7 @@ pub fn gather_move_from_pat(bccx: @BorrowckCtxt,
                                  MovePat(move_pat), cmt);
 }
 
-fn gather_move_from_expr_or_pat(bccx: @BorrowckCtxt,
+fn gather_move_from_expr_or_pat(bccx: &BorrowckCtxt,
                                 move_data: &mut MoveData,
                                 move_id: ast::NodeId,
                                 move_kind: MoveKind,
@@ -66,7 +66,7 @@ fn gather_move_from_expr_or_pat(bccx: @BorrowckCtxt,
     }
 }
 
-pub fn gather_captures(bccx: @BorrowckCtxt,
+pub fn gather_captures(bccx: &BorrowckCtxt,
                        move_data: &mut MoveData,
                        closure_expr: @ast::Expr) {
     let captured_vars = bccx.capture_map.get(&closure_expr.id);
@@ -83,7 +83,7 @@ pub fn gather_captures(bccx: @BorrowckCtxt,
     }
 }
 
-pub fn gather_assignment(bccx: @BorrowckCtxt,
+pub fn gather_assignment(bccx: &BorrowckCtxt,
                          move_data: &mut MoveData,
                          assignment_id: ast::NodeId,
                          assignment_span: Span,
@@ -96,7 +96,7 @@ pub fn gather_assignment(bccx: @BorrowckCtxt,
                              assignee_id);
 }
 
-fn check_is_legal_to_move_from(bccx: @BorrowckCtxt,
+fn check_is_legal_to_move_from(bccx: &BorrowckCtxt,
                                cmt0: mc::cmt,
                                cmt: mc::cmt) -> bool {
     match cmt.cat {

src/librustc/middle/borrowck/gather_loans/lifetime.rs

@@ -20,7 +20,7 @@ use syntax::ast;
 use syntax::codemap::Span;
 use util::ppaux::{note_and_explain_region};
 
-pub fn guarantee_lifetime(bccx: @BorrowckCtxt,
+pub fn guarantee_lifetime(bccx: &BorrowckCtxt,
                           item_scope_id: ast::NodeId,
                           root_scope_id: ast::NodeId,
                           span: Span,
@@ -42,8 +42,8 @@ pub fn guarantee_lifetime(bccx: @BorrowckCtxt,
 ///////////////////////////////////////////////////////////////////////////
 // Private
 
-struct GuaranteeLifetimeContext {
+struct GuaranteeLifetimeContext<'self> {
-    bccx: @BorrowckCtxt,
+    bccx: &'self BorrowckCtxt,
 
     // the node id of the function body for the enclosing item
     item_scope_id: ast::NodeId,
@@ -58,7 +58,7 @@ struct GuaranteeLifetimeContext {
     cmt_original: mc::cmt
 }
 
-impl GuaranteeLifetimeContext {
+impl<'self> GuaranteeLifetimeContext<'self> {
     fn tcx(&self) -> ty::ctxt {
         self.bccx.tcx
     }

src/librustc/middle/borrowck/gather_loans/mod.rs

@@ -64,8 +64,8 @@ mod gather_moves;
 /// No good.  Instead what will happen is that `root_ub` will be set to the
 /// body of the while loop and we will refuse to root the pointer `&*x`
 /// because it would have to be rooted for a region greater than `root_ub`.
-struct GatherLoanCtxt {
+struct GatherLoanCtxt<'self> {
-    bccx: @BorrowckCtxt,
+    bccx: &'self BorrowckCtxt,
     id_range: id_range,
     move_data: @mut move_data::MoveData,
     all_loans: @mut ~[Loan],
@@ -73,7 +73,7 @@ struct GatherLoanCtxt {
     repeating_ids: ~[ast::NodeId]
 }
 
-impl visit::Visitor<()> for GatherLoanCtxt {
+impl<'self> visit::Visitor<()> for GatherLoanCtxt<'self> {
     fn visit_expr(&mut self, ex:@Expr, _:()) {
         gather_loans_in_expr(self, ex);
     }
@@ -100,7 +100,7 @@ impl visit::Visitor<()> for GatherLoanCtxt {
     fn visit_item(&mut self, _:@ast::item, _:()) { }
 }
 
-pub fn gather_loans(bccx: @BorrowckCtxt,
+pub fn gather_loans(bccx: &BorrowckCtxt,
                     decl: &ast::fn_decl,
                     body: &ast::Block)
                     -> (id_range, @mut ~[Loan], @mut move_data::MoveData) {
@@ -315,7 +315,7 @@ fn gather_loans_in_expr(this: &mut GatherLoanCtxt,
     }
 }
 
-impl GatherLoanCtxt {
+impl<'self> GatherLoanCtxt<'self> {
     pub fn tcx(&self) -> ty::ctxt { self.bccx.tcx }
 
     pub fn push_repeating_id(&mut self, id: ast::NodeId) {
@@ -532,7 +532,7 @@ impl GatherLoanCtxt {
             //    }
         // }
 
-        fn check_mutability(bccx: @BorrowckCtxt,
+        fn check_mutability(bccx: &BorrowckCtxt,
                             borrow_span: Span,
                             cmt: mc::cmt,
                             req_mutbl: LoanMutability) {

src/librustc/middle/borrowck/gather_loans/restrictions.rs

@@ -23,7 +23,7 @@ pub enum RestrictionResult {
     SafeIf(@LoanPath, ~[Restriction])
 }
 
-pub fn compute_restrictions(bccx: @BorrowckCtxt,
+pub fn compute_restrictions(bccx: &BorrowckCtxt,
                             span: Span,
                             cmt: mc::cmt,
                             restr: RestrictionSet) -> RestrictionResult {
@@ -39,13 +39,13 @@ pub fn compute_restrictions(bccx: @BorrowckCtxt,
 ///////////////////////////////////////////////////////////////////////////
 // Private
 
-struct RestrictionsContext {
+struct RestrictionsContext<'self> {
-    bccx: @BorrowckCtxt,
+    bccx: &'self BorrowckCtxt,
     span: Span,
     cmt_original: mc::cmt
 }
 
-impl RestrictionsContext {
+impl<'self> RestrictionsContext<'self> {
     fn tcx(&self) -> ty::ctxt {
         self.bccx.tcx
     }

src/librustc/middle/borrowck/mod.rs

@@ -61,12 +61,10 @@ impl Clone for LoanDataFlowOperator {
 
 pub type LoanDataFlow = DataFlowContext<LoanDataFlowOperator>;
 
-struct BorrowckVisitor;
+impl Visitor<()> for BorrowckCtxt {
-
-impl Visitor<@BorrowckCtxt> for BorrowckVisitor {
     fn visit_fn(&mut self, fk:&fn_kind, fd:&fn_decl,
-                b:&Block, s:Span, n:NodeId, e:@BorrowckCtxt) {
+                b:&Block, s:Span, n:NodeId, _:()) {
-        borrowck_fn(self, fk, fd, b, s, n, e);
+        borrowck_fn(self, fk, fd, b, s, n);
     }
 }
 
@@ -78,7 +76,7 @@ pub fn check_crate(
     capture_map: moves::CaptureMap,
     crate: &ast::Crate) -> (root_map, write_guard_map)
 {
-    let bccx = @BorrowckCtxt {
+    let mut bccx = BorrowckCtxt {
         tcx: tcx,
         method_map: method_map,
         moves_map: moves_map,
@@ -96,9 +94,9 @@ pub fn check_crate(
             guaranteed_paths: 0,
         }
     };
+    let bccx = &mut bccx;
 
-    let mut v = BorrowckVisitor;
+    visit::walk_crate(bccx, crate, ());
-    visit::walk_crate(&mut v, crate, bccx);
 
     if tcx.sess.borrowck_stats() {
         io::println("--- borrowck stats ---");
@@ -116,20 +114,19 @@ pub fn check_crate(
 
     return (bccx.root_map, bccx.write_guard_map);
 
-    fn make_stat(bccx: &BorrowckCtxt, stat: uint) -> ~str {
+    fn make_stat(bccx: &mut BorrowckCtxt, stat: uint) -> ~str {
         let stat_f = stat as float;
         let total = bccx.stats.guaranteed_paths as float;
         fmt!("%u (%.0f%%)", stat  , stat_f * 100f / total)
     }
 }
 
-fn borrowck_fn(v: &mut BorrowckVisitor,
+fn borrowck_fn(this: &mut BorrowckCtxt,
                fk: &visit::fn_kind,
                decl: &ast::fn_decl,
                body: &ast::Block,
                sp: Span,
-               id: ast::NodeId,
+               id: ast::NodeId) {
-               this: @BorrowckCtxt) {
     match fk {
         &visit::fk_anon(*) |
         &visit::fk_fn_block(*) => {
@@ -166,7 +163,7 @@ fn borrowck_fn(v: &mut BorrowckVisitor,
         }
     }
 
-    visit::walk_fn(v, fk, decl, body, sp, id, this);
+    visit::walk_fn(this, fk, decl, body, sp, id, ());
 }
 
 // ----------------------------------------------------------------------