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Remove ExprSlice by hacking the compiler
[breaking-change] The `mut` in slices is now redundant. Mutability is 'inferred' from position. This means that if mutability is only obvious from the type, you will need to use explicit calls to the slicing methods.
1 parent ed8f503 commit 4e2afb0

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18 files changed

+254
-319
lines changed

18 files changed

+254
-319
lines changed

‎src/libcore/slice.rs

+2-2
Original file line numberDiff line numberDiff line change
@@ -990,7 +990,7 @@ impl<'a, T, P> Iterator<&'a mut [T]> for MutSplits<'a, T, P> where P: FnMut(&T)
990990
Some(idx) => {
991991
let tmp = mem::replace(&mut self.v, &mut []);
992992
let (head, tail) = tmp.split_at_mut(idx);
993-
self.v = tail[mut 1..];
993+
self.v = tail.slice_from_mut(1);
994994
Some(head)
995995
}
996996
}
@@ -1026,7 +1026,7 @@ impl<'a, T, P> DoubleEndedIterator<&'a mut [T]> for MutSplits<'a, T, P> where
10261026
let tmp = mem::replace(&mut self.v, &mut []);
10271027
let (head, tail) = tmp.split_at_mut(idx);
10281028
self.v = head;
1029-
Some(tail[mut 1..])
1029+
Some(tail.slice_from_mut(1))
10301030
}
10311031
}
10321032
}

‎src/librustc/middle/cfg/construct.rs

-7
Original file line numberDiff line numberDiff line change
@@ -432,13 +432,6 @@ impl<'a, 'tcx> CFGBuilder<'a, 'tcx> {
432432
self.call(expr, pred, &**l, Some(&**r).into_iter())
433433
}
434434

435-
ast::ExprSlice(ref base, ref start, ref end, _) => {
436-
self.call(expr,
437-
pred,
438-
&**base,
439-
start.iter().chain(end.iter()).map(|x| &**x))
440-
}
441-
442435
ast::ExprRange(ref start, ref end) => {
443436
let fields = start.as_ref().map(|e| &**e).into_iter()
444437
.chain(end.as_ref().map(|e| &**e).into_iter());

‎src/librustc/middle/expr_use_visitor.rs

+22-15
Original file line numberDiff line numberDiff line change
@@ -431,24 +431,31 @@ impl<'d,'t,'tcx,TYPER:mc::Typer<'tcx>> ExprUseVisitor<'d,'t,'tcx,TYPER> {
431431
}
432432

433433
ast::ExprIndex(ref lhs, ref rhs) => { // lhs[rhs]
434-
if !self.walk_overloaded_operator(expr, &**lhs, vec![&**rhs], PassArgs::ByRef) {
435-
self.select_from_expr(&**lhs);
436-
self.consume_expr(&**rhs);
434+
match rhs.node {
435+
ast::ExprRange(ref start, ref end) => {
436+
// Hacked slicing syntax (KILLME).
437+
let args = match (start, end) {
438+
(&Some(ref e1), &Some(ref e2)) => vec![&**e1, &**e2],
439+
(&Some(ref e), &None) => vec![&**e],
440+
(&None, &Some(ref e)) => vec![&**e],
441+
(&None, &None) => Vec::new()
442+
};
443+
let overloaded =
444+
self.walk_overloaded_operator(expr, &**lhs, args, PassArgs::ByRef);
445+
assert!(overloaded);
446+
}
447+
_ => {
448+
if !self.walk_overloaded_operator(expr,
449+
&**lhs,
450+
vec![&**rhs],
451+
PassArgs::ByRef) {
452+
self.select_from_expr(&**lhs);
453+
self.consume_expr(&**rhs);
454+
}
455+
}
437456
}
438457
}
439458

440-
ast::ExprSlice(ref base, ref start, ref end, _) => { // base[start..end]
441-
let args = match (start, end) {
442-
(&Some(ref e1), &Some(ref e2)) => vec![&**e1, &**e2],
443-
(&Some(ref e), &None) => vec![&**e],
444-
(&None, &Some(ref e)) => vec![&**e],
445-
(&None, &None) => Vec::new()
446-
};
447-
let overloaded =
448-
self.walk_overloaded_operator(expr, &**base, args, PassArgs::ByRef);
449-
assert!(overloaded);
450-
}
451-
452459
ast::ExprRange(ref start, ref end) => {
453460
start.as_ref().map(|e| self.consume_expr(&**e));
454461
end.as_ref().map(|e| self.consume_expr(&**e));

‎src/librustc/middle/liveness.rs

+2-8
Original file line numberDiff line numberDiff line change
@@ -514,7 +514,7 @@ fn visit_expr(ir: &mut IrMaps, expr: &Expr) {
514514
ast::ExprBlock(..) | ast::ExprAssign(..) | ast::ExprAssignOp(..) |
515515
ast::ExprMac(..) | ast::ExprStruct(..) | ast::ExprRepeat(..) |
516516
ast::ExprParen(..) | ast::ExprInlineAsm(..) | ast::ExprBox(..) |
517-
ast::ExprSlice(..) | ast::ExprRange(..) => {
517+
ast::ExprRange(..) => {
518518
visit::walk_expr(ir, expr);
519519
}
520520
}
@@ -1191,12 +1191,6 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
11911191
self.propagate_through_expr(&**l, r_succ)
11921192
}
11931193

1194-
ast::ExprSlice(ref e1, ref e2, ref e3, _) => {
1195-
let succ = e3.as_ref().map_or(succ, |e| self.propagate_through_expr(&**e, succ));
1196-
let succ = e2.as_ref().map_or(succ, |e| self.propagate_through_expr(&**e, succ));
1197-
self.propagate_through_expr(&**e1, succ)
1198-
}
1199-
12001194
ast::ExprRange(ref e1, ref e2) => {
12011195
let succ = e2.as_ref().map_or(succ, |e| self.propagate_through_expr(&**e, succ));
12021196
e1.as_ref().map_or(succ, |e| self.propagate_through_expr(&**e, succ))
@@ -1495,7 +1489,7 @@ fn check_expr(this: &mut Liveness, expr: &Expr) {
14951489
ast::ExprBlock(..) | ast::ExprMac(..) | ast::ExprAddrOf(..) |
14961490
ast::ExprStruct(..) | ast::ExprRepeat(..) | ast::ExprParen(..) |
14971491
ast::ExprClosure(..) | ast::ExprPath(..) | ast::ExprBox(..) |
1498-
ast::ExprSlice(..) | ast::ExprRange(..) => {
1492+
ast::ExprRange(..) => {
14991493
visit::walk_expr(this, expr);
15001494
}
15011495
ast::ExprIfLet(..) => {

‎src/librustc/middle/mem_categorization.rs

+23-15
Original file line numberDiff line numberDiff line change
@@ -500,21 +500,29 @@ impl<'t,'tcx,TYPER:Typer<'tcx>> MemCategorizationContext<'t,TYPER> {
500500
self.cat_tup_field(expr, base_cmt, idx.node, expr_ty)
501501
}
502502

503-
ast::ExprIndex(ref base, _) => {
504-
let method_call = ty::MethodCall::expr(expr.id());
505-
match self.typer.node_method_ty(method_call) {
506-
Some(method_ty) => {
507-
// If this is an index implemented by a method call, then it will
508-
// include an implicit deref of the result.
509-
let ret_ty = ty::ty_fn_ret(method_ty).unwrap();
510-
self.cat_deref(expr,
511-
self.cat_rvalue_node(expr.id(),
512-
expr.span(),
513-
ret_ty), 1, true)
503+
ast::ExprIndex(ref base, ref idx) => {
504+
match idx.node {
505+
ast::ExprRange(..) => {
506+
// Slicing syntax special case (KILLME).
507+
self.cat_rvalue_node(expr.id(), expr.span(), expr_ty)
514508
}
515-
None => {
516-
let base_cmt = self.cat_expr(&**base);
517-
self.cat_index(expr, base_cmt)
509+
_ => {
510+
let method_call = ty::MethodCall::expr(expr.id());
511+
match self.typer.node_method_ty(method_call) {
512+
Some(method_ty) => {
513+
// If this is an index implemented by a method call, then it will
514+
// include an implicit deref of the result.
515+
let ret_ty = ty::ty_fn_ret(method_ty).unwrap();
516+
self.cat_deref(expr,
517+
self.cat_rvalue_node(expr.id(),
518+
expr.span(),
519+
ret_ty), 1, true)
520+
}
521+
None => {
522+
let base_cmt = if_ok!(self.cat_expr(&**base));
523+
self.cat_index(expr, base_cmt)
524+
}
525+
}
518526
}
519527
}
520528
}
@@ -531,7 +539,7 @@ impl<'t,'tcx,TYPER:Typer<'tcx>> MemCategorizationContext<'t,TYPER> {
531539
ast::ExprAddrOf(..) | ast::ExprCall(..) |
532540
ast::ExprAssign(..) | ast::ExprAssignOp(..) |
533541
ast::ExprClosure(..) | ast::ExprRet(..) |
534-
ast::ExprUnary(..) | ast::ExprSlice(..) | ast::ExprRange(..) |
542+
ast::ExprUnary(..) | ast::ExprRange(..) |
535543
ast::ExprMethodCall(..) | ast::ExprCast(..) |
536544
ast::ExprVec(..) | ast::ExprTup(..) | ast::ExprIf(..) |
537545
ast::ExprBinary(..) | ast::ExprWhile(..) |

‎src/librustc/middle/ty.rs

+1-5
Original file line numberDiff line numberDiff line change
@@ -4322,9 +4322,6 @@ pub fn expr_kind(tcx: &ctxt, expr: &ast::Expr) -> ExprKind {
43224322
// the index method invoked for `a[i]` always yields an `&T`
43234323
ast::ExprIndex(..) => LvalueExpr,
43244324

4325-
// the slice method invoked for `a[..]` always yields an `&T`
4326-
ast::ExprSlice(..) => LvalueExpr,
4327-
43284325
// `for` loops are statements
43294326
ast::ExprForLoop(..) => RvalueStmtExpr,
43304327

@@ -4389,8 +4386,7 @@ pub fn expr_kind(tcx: &ctxt, expr: &ast::Expr) -> ExprKind {
43894386
ast::ExprUnary(ast::UnDeref, _) |
43904387
ast::ExprField(..) |
43914388
ast::ExprTupField(..) |
4392-
ast::ExprIndex(..) |
4393-
ast::ExprSlice(..) => {
4389+
ast::ExprIndex(..) => {
43944390
LvalueExpr
43954391
}
43964392

‎src/librustc_back/svh.rs

-2
Original file line numberDiff line numberDiff line change
@@ -246,7 +246,6 @@ mod svh_visitor {
246246
SawExprAssign,
247247
SawExprAssignOp(ast::BinOp),
248248
SawExprIndex,
249-
SawExprSlice,
250249
SawExprRange,
251250
SawExprPath,
252251
SawExprAddrOf(ast::Mutability),
@@ -280,7 +279,6 @@ mod svh_visitor {
280279
ExprField(_, id) => SawExprField(content(id.node)),
281280
ExprTupField(_, id) => SawExprTupField(id.node),
282281
ExprIndex(..) => SawExprIndex,
283-
ExprSlice(..) => SawExprSlice,
284282
ExprRange(..) => SawExprRange,
285283
ExprPath(..) => SawExprPath,
286284
ExprAddrOf(m, _) => SawExprAddrOf(m),

‎src/librustc_trans/trans/cleanup.rs

+5-3
Original file line numberDiff line numberDiff line change
@@ -24,7 +24,8 @@ use trans::common;
2424
use trans::common::{Block, FunctionContext, ExprId, NodeInfo};
2525
use trans::debuginfo;
2626
use trans::glue;
27-
use middle::region;
27+
// Temporary due to slicing syntax hacks (KILLME)
28+
//use middle::region;
2829
use trans::type_::Type;
2930
use middle::ty::{mod, Ty};
3031
use std::fmt;
@@ -128,15 +129,16 @@ impl<'blk, 'tcx> CleanupMethods<'blk, 'tcx> for FunctionContext<'blk, 'tcx> {
128129
// excluding id's that correspond to closure bodies only). For
129130
// now we just say that if there is already an AST scope on the stack,
130131
// this new AST scope had better be its immediate child.
131-
let top_scope = self.top_ast_scope();
132+
// Temporarily removed due to slicing syntax hacks (KILLME).
133+
/*let top_scope = self.top_ast_scope();
132134
if top_scope.is_some() {
133135
assert_eq!(self.ccx
134136
.tcx()
135137
.region_maps
136138
.opt_encl_scope(region::CodeExtent::from_node_id(debug_loc.id))
137139
.map(|s|s.node_id()),
138140
top_scope);
139-
}
141+
}*/
140142

141143
self.push_scope(CleanupScope::new(AstScopeKind(debug_loc.id),
142144
Some(debug_loc)));

‎src/librustc_trans/trans/debuginfo.rs

+1-7
Original file line numberDiff line numberDiff line change
@@ -3533,18 +3533,12 @@ fn create_scope_map(cx: &CrateContext,
35333533
}
35343534

35353535
ast::ExprAssignOp(_, ref lhs, ref rhs) |
3536-
ast::ExprIndex(ref lhs, ref rhs) |
3536+
ast::ExprIndex(ref lhs, ref rhs) |
35373537
ast::ExprBinary(_, ref lhs, ref rhs) => {
35383538
walk_expr(cx, &**lhs, scope_stack, scope_map);
35393539
walk_expr(cx, &**rhs, scope_stack, scope_map);
35403540
}
35413541

3542-
ast::ExprSlice(ref base, ref start, ref end, _) => {
3543-
walk_expr(cx, &**base, scope_stack, scope_map);
3544-
start.as_ref().map(|x| walk_expr(cx, &**x, scope_stack, scope_map));
3545-
end.as_ref().map(|x| walk_expr(cx, &**x, scope_stack, scope_map));
3546-
}
3547-
35483542
ast::ExprRange(ref start, ref end) => {
35493543
start.as_ref().map(|e| walk_expr(cx, &**e, scope_stack, scope_map));
35503544
end.as_ref().map(|e| walk_expr(cx, &**e, scope_stack, scope_map));

‎src/librustc_trans/trans/expr.rs

+34-30
Original file line numberDiff line numberDiff line change
@@ -585,36 +585,40 @@ fn trans_datum_unadjusted<'blk, 'tcx>(bcx: Block<'blk, 'tcx>,
585585
trans_rec_tup_field(bcx, &**base, idx.node)
586586
}
587587
ast::ExprIndex(ref base, ref idx) => {
588-
trans_index(bcx, expr, &**base, &**idx, MethodCall::expr(expr.id))
589-
}
590-
ast::ExprSlice(ref base, ref start, ref end, _) => {
591-
let _icx = push_ctxt("trans_slice");
592-
let ccx = bcx.ccx();
593-
594-
let method_call = MethodCall::expr(expr.id);
595-
let method_ty = ccx.tcx()
596-
.method_map
597-
.borrow()
598-
.get(&method_call)
599-
.map(|method| method.ty);
600-
let base_datum = unpack_datum!(bcx, trans(bcx, &**base));
601-
602-
let mut args = vec![];
603-
start.as_ref().map(|e| args.push((unpack_datum!(bcx, trans(bcx, &**e)), e.id)));
604-
end.as_ref().map(|e| args.push((unpack_datum!(bcx, trans(bcx, &**e)), e.id)));
605-
606-
let result_ty = ty::ty_fn_ret(monomorphize_type(bcx, method_ty.unwrap())).unwrap();
607-
let scratch = rvalue_scratch_datum(bcx, result_ty, "trans_slice");
608-
609-
unpack_result!(bcx,
610-
trans_overloaded_op(bcx,
611-
expr,
612-
method_call,
613-
base_datum,
614-
args,
615-
Some(SaveIn(scratch.val)),
616-
true));
617-
DatumBlock::new(bcx, scratch.to_expr_datum())
588+
match idx.node {
589+
ast::ExprRange(ref start, ref end) => {
590+
// Special case for slicing syntax (KILLME).
591+
let _icx = push_ctxt("trans_slice");
592+
let ccx = bcx.ccx();
593+
594+
let method_call = MethodCall::expr(expr.id);
595+
let method_ty = ccx.tcx()
596+
.method_map
597+
.borrow()
598+
.get(&method_call)
599+
.map(|method| method.ty);
600+
let base_datum = unpack_datum!(bcx, trans(bcx, &**base));
601+
602+
let mut args = vec![];
603+
start.as_ref().map(|e| args.push((unpack_datum!(bcx, trans(bcx, &**e)), e.id)));
604+
end.as_ref().map(|e| args.push((unpack_datum!(bcx, trans(bcx, &**e)), e.id)));
605+
606+
let result_ty = ty::ty_fn_ret(monomorphize_type(bcx,
607+
method_ty.unwrap())).unwrap();
608+
let scratch = rvalue_scratch_datum(bcx, result_ty, "trans_slice");
609+
610+
unpack_result!(bcx,
611+
trans_overloaded_op(bcx,
612+
expr,
613+
method_call,
614+
base_datum,
615+
args,
616+
Some(SaveIn(scratch.val)),
617+
true));
618+
DatumBlock::new(bcx, scratch.to_expr_datum())
619+
}
620+
_ => trans_index(bcx, expr, &**base, &**idx, MethodCall::expr(expr.id))
621+
}
618622
}
619623
ast::ExprBox(_, ref contents) => {
620624
// Special case for `Box<T>`

‎src/librustc_typeck/check/method/confirm.rs

-1
Original file line numberDiff line numberDiff line change
@@ -488,7 +488,6 @@ impl<'a,'tcx> ConfirmContext<'a,'tcx> {
488488
ast::ExprParen(ref expr) |
489489
ast::ExprField(ref expr, _) |
490490
ast::ExprTupField(ref expr, _) |
491-
ast::ExprSlice(ref expr, _, _, _) |
492491
ast::ExprIndex(ref expr, _) |
493492
ast::ExprUnary(ast::UnDeref, ref expr) => exprs.push(&**expr),
494493
_ => break,

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