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Merged
merged 1 commit into from
Jun 16, 2016
Merged

prefer if let to match with None => () arm in some places #34268

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41 changes: 17 additions & 24 deletions src/librustc/hir/print.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -1728,12 +1728,9 @@ impl<'a> State<'a> {
}
}
self.print_name(path1.node)?;
match *sub {
Some(ref p) => {
word(&mut self.s, "@")?;
self.print_pat(&p)?;
}
None => (),
if let Some(ref p) = *sub {
word(&mut self.s, "@")?;
self.print_pat(&p)?;
}
}
PatKind::TupleStruct(ref path, ref elts, ddpos) => {
Expand Down Expand Up @@ -2246,25 +2243,21 @@ impl<'a> State<'a> {
Some(cm) => cm,
_ => return Ok(()),
};
match self.next_comment() {
Some(ref cmnt) => {
if (*cmnt).style != comments::Trailing {
return Ok(());
}
let span_line = cm.lookup_char_pos(span.hi);
let comment_line = cm.lookup_char_pos((*cmnt).pos);
let mut next = (*cmnt).pos + BytePos(1);
match next_pos {
None => (),
Some(p) => next = p,
}
if span.hi < (*cmnt).pos && (*cmnt).pos < next &&
span_line.line == comment_line.line {
self.print_comment(cmnt)?;
self.cur_cmnt_and_lit.cur_cmnt += 1;
}
if let Some(ref cmnt) = self.next_comment() {
if (*cmnt).style != comments::Trailing {
return Ok(());
}
let span_line = cm.lookup_char_pos(span.hi);
let comment_line = cm.lookup_char_pos((*cmnt).pos);
let mut next = (*cmnt).pos + BytePos(1);
if let Some(p) = next_pos {
next = p;
}
if span.hi < (*cmnt).pos && (*cmnt).pos < next &&
span_line.line == comment_line.line {
self.print_comment(cmnt)?;
self.cur_cmnt_and_lit.cur_cmnt += 1;
}
_ => (),
}
Ok(())
}
Expand Down
11 changes: 4 additions & 7 deletions src/librustc/infer/error_reporting.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -1856,20 +1856,18 @@ fn lifetimes_in_scope<'a, 'gcx, 'tcx>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
},
None => None
};
if method_id_opt.is_some() {
let method_id = method_id_opt.unwrap();
if let Some(method_id) = method_id_opt {
let parent = tcx.map.get_parent(method_id);
match tcx.map.find(parent) {
Some(node) => match node {
if let Some(node) = tcx.map.find(parent) {
match node {
ast_map::NodeItem(item) => match item.node {
hir::ItemImpl(_, _, ref gen, _, _, _) => {
taken.extend_from_slice(&gen.lifetimes);
}
_ => ()
},
_ => ()
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I believe you could also rewrite these two matchs as if lets (optional, of course)

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(Yes, I was deliberately being conservative in this submission and only targeting the most obvious Some(x)/None matches.)

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Makes sense.

},
None => ()
}
}
}
return taken;
Expand Down Expand Up @@ -1938,4 +1936,3 @@ fn name_to_dummy_lifetime(name: ast::Name) -> hir::Lifetime {
span: codemap::DUMMY_SP,
name: name }
}

32 changes: 13 additions & 19 deletions src/librustc/middle/dead.rs
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Expand Up @@ -160,12 +160,9 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
}
scanned.insert(id);

match self.tcx.map.find(id) {
Some(ref node) => {
self.live_symbols.insert(id);
self.visit_node(node);
}
None => (),
if let Some(ref node) = self.tcx.map.find(id) {
self.live_symbols.insert(id);
self.visit_node(node);
}
}
}
Expand Down Expand Up @@ -372,9 +369,8 @@ fn create_and_seed_worklist<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
}

// Seed entry point
match *tcx.sess.entry_fn.borrow() {
Some((id, _)) => worklist.push(id),
None => ()
if let Some((id, _)) = *tcx.sess.entry_fn.borrow() {
worklist.push(id);
}

// Seed implemented trait items
Expand Down Expand Up @@ -464,16 +460,14 @@ impl<'a, 'tcx> DeadVisitor<'a, 'tcx> {
// method of a private type is used, but the type itself is never
// called directly.
let impl_items = self.tcx.impl_items.borrow();
match self.tcx.inherent_impls.borrow().get(&self.tcx.map.local_def_id(id)) {
None => (),
Some(impl_list) => {
for impl_did in impl_list.iter() {
for item_did in impl_items.get(impl_did).unwrap().iter() {
if let Some(item_node_id) =
self.tcx.map.as_local_node_id(item_did.def_id()) {
if self.live_symbols.contains(&item_node_id) {
return true;
}
if let Some(impl_list) =
self.tcx.inherent_impls.borrow().get(&self.tcx.map.local_def_id(id)) {
for impl_did in impl_list.iter() {
for item_did in impl_items.get(impl_did).unwrap().iter() {
if let Some(item_node_id) =
self.tcx.map.as_local_node_id(item_did.def_id()) {
if self.live_symbols.contains(&item_node_id) {
return true;
}
}
}
Expand Down
15 changes: 6 additions & 9 deletions src/librustc_borrowck/borrowck/gather_loans/gather_moves.rs
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Expand Up @@ -122,15 +122,12 @@ fn gather_move<'a, 'tcx>(bccx: &BorrowckCtxt<'a, 'tcx>,

let potentially_illegal_move =
check_and_get_illegal_move_origin(bccx, &move_info.cmt);
match potentially_illegal_move {
Some(illegal_move_origin) => {
debug!("illegal_move_origin={:?}", illegal_move_origin);
let error = MoveError::with_move_info(illegal_move_origin,
move_info.span_path_opt);
move_error_collector.add_error(error);
return
}
None => ()
if let Some(illegal_move_origin) = potentially_illegal_move {
debug!("illegal_move_origin={:?}", illegal_move_origin);
let error = MoveError::with_move_info(illegal_move_origin,
move_info.span_path_opt);
move_error_collector.add_error(error);
return;
}

match opt_loan_path(&move_info.cmt) {
Expand Down
43 changes: 20 additions & 23 deletions src/librustc_metadata/creader.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -929,29 +929,26 @@ impl<'a> LocalCrateReader<'a> {
return;
}

match self.creader.extract_crate_info(i) {
Some(info) => {
let (cnum, _, _) = self.creader.resolve_crate(&None,
&info.ident,
&info.name,
None,
i.span,
PathKind::Crate,
true);

let def_id = self.definitions.opt_local_def_id(i.id).unwrap();
let len = self.definitions.def_path(def_id.index).data.len();

self.creader.update_extern_crate(cnum,
ExternCrate {
def_id: def_id,
span: i.span,
direct: true,
path_len: len,
});
self.cstore.add_extern_mod_stmt_cnum(info.id, cnum);
}
None => ()
if let Some(info) = self.creader.extract_crate_info(i) {
let (cnum, _, _) = self.creader.resolve_crate(&None,
&info.ident,
&info.name,
None,
i.span,
PathKind::Crate,
true);

let def_id = self.definitions.opt_local_def_id(i.id).unwrap();
let len = self.definitions.def_path(def_id.index).data.len();

self.creader.update_extern_crate(cnum,
ExternCrate {
def_id: def_id,
span: i.span,
direct: true,
path_len: len,
});
self.cstore.add_extern_mod_stmt_cnum(info.id, cnum);
}
}
ast::ItemKind::ForeignMod(ref fm) => self.process_foreign_mod(i, fm),
Expand Down
19 changes: 8 additions & 11 deletions src/librustc_trans/base.rs
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Expand Up @@ -2252,17 +2252,14 @@ pub fn update_linkage(ccx: &CrateContext,
}

fn set_global_section(ccx: &CrateContext, llval: ValueRef, i: &hir::Item) {
match attr::first_attr_value_str_by_name(&i.attrs, "link_section") {
Some(sect) => {
if contains_null(&sect) {
ccx.sess().fatal(&format!("Illegal null byte in link_section value: `{}`", &sect));
}
unsafe {
let buf = CString::new(sect.as_bytes()).unwrap();
llvm::LLVMSetSection(llval, buf.as_ptr());
}
},
None => ()
if let Some(sect) = attr::first_attr_value_str_by_name(&i.attrs, "link_section") {
if contains_null(&sect) {
ccx.sess().fatal(&format!("Illegal null byte in link_section value: `{}`", &sect));
}
unsafe {
let buf = CString::new(sect.as_bytes()).unwrap();
llvm::LLVMSetSection(llval, buf.as_ptr());
}
}
}

Expand Down
5 changes: 2 additions & 3 deletions src/librustc_trans/debuginfo/metadata.rs
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Expand Up @@ -874,9 +874,8 @@ pub fn unknown_file_metadata(cx: &CrateContext) -> DIFile {
}

fn file_metadata_(cx: &CrateContext, key: &str, file_name: &str, work_dir: &str) -> DIFile {
match debug_context(cx).created_files.borrow().get(key) {
Some(file_metadata) => return *file_metadata,
None => ()
if let Some(file_metadata) = debug_context(cx).created_files.borrow().get(key) {
return *file_metadata;
}

debug!("file_metadata: file_name: {}, work_dir: {}", file_name, work_dir);
Expand Down
9 changes: 3 additions & 6 deletions src/librustc_trans/monomorphize.rs
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Expand Up @@ -50,12 +50,9 @@ pub fn monomorphic_fn<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>,
let mono_ty = apply_param_substs(ccx.tcx(), psubsts, &item_ty);
debug!("mono_ty = {:?} (post-substitution)", mono_ty);

match ccx.instances().borrow().get(&instance) {
Some(&val) => {
debug!("leaving monomorphic fn {:?}", instance);
return (val, mono_ty);
}
None => ()
if let Some(&val) = ccx.instances().borrow().get(&instance) {
debug!("leaving monomorphic fn {:?}", instance);
return (val, mono_ty);
}

debug!("monomorphic_fn({:?})", instance);
Expand Down
21 changes: 9 additions & 12 deletions src/libsyntax/parse/parser.rs
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Expand Up @@ -5430,18 +5430,15 @@ impl<'a> Parser<'a> {
name: String,
id_sp: Span) -> PResult<'a, (ast::ItemKind, Vec<ast::Attribute> )> {
let mut included_mod_stack = self.sess.included_mod_stack.borrow_mut();
match included_mod_stack.iter().position(|p| *p == path) {
Some(i) => {
let mut err = String::from("circular modules: ");
let len = included_mod_stack.len();
for p in &included_mod_stack[i.. len] {
err.push_str(&p.to_string_lossy());
err.push_str(" -> ");
}
err.push_str(&path.to_string_lossy());
return Err(self.span_fatal(id_sp, &err[..]));
}
None => ()
if let Some(i) = included_mod_stack.iter().position(|p| *p == path) {
let mut err = String::from("circular modules: ");
let len = included_mod_stack.len();
for p in &included_mod_stack[i.. len] {
err.push_str(&p.to_string_lossy());
err.push_str(" -> ");
}
err.push_str(&path.to_string_lossy());
return Err(self.span_fatal(id_sp, &err[..]));
}
included_mod_stack.push(path.clone());
drop(included_mod_stack);
Expand Down
34 changes: 15 additions & 19 deletions src/libsyntax/print/pprust.rs
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Expand Up @@ -2459,12 +2459,9 @@ impl<'a> State<'a> {
}
}
self.print_ident(path1.node)?;
match *sub {
Some(ref p) => {
word(&mut self.s, "@")?;
self.print_pat(&p)?;
}
None => ()
if let Some(ref p) = *sub {
word(&mut self.s, "@")?;
self.print_pat(&p)?;
}
}
PatKind::TupleStruct(ref path, ref elts, ddpos) => {
Expand Down Expand Up @@ -3008,20 +3005,19 @@ impl<'a> State<'a> {
Some(cm) => cm,
_ => return Ok(())
};
match self.next_comment() {
Some(ref cmnt) => {
if (*cmnt).style != comments::Trailing { return Ok(()) }
let span_line = cm.lookup_char_pos(span.hi);
let comment_line = cm.lookup_char_pos((*cmnt).pos);
let mut next = (*cmnt).pos + BytePos(1);
match next_pos { None => (), Some(p) => next = p }
if span.hi < (*cmnt).pos && (*cmnt).pos < next &&
span_line.line == comment_line.line {
self.print_comment(cmnt)?;
self.cur_cmnt_and_lit.cur_cmnt += 1;
}
if let Some(ref cmnt) = self.next_comment() {
if (*cmnt).style != comments::Trailing { return Ok(()) }
let span_line = cm.lookup_char_pos(span.hi);
let comment_line = cm.lookup_char_pos((*cmnt).pos);
let mut next = (*cmnt).pos + BytePos(1);
if let Some(p) = next_pos {
next = p;
}
if span.hi < (*cmnt).pos && (*cmnt).pos < next &&
span_line.line == comment_line.line {
self.print_comment(cmnt)?;
self.cur_cmnt_and_lit.cur_cmnt += 1;
}
_ => ()
}
Ok(())
}
Expand Down
10 changes: 4 additions & 6 deletions src/libsyntax/util/interner.rs
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Expand Up @@ -47,9 +47,8 @@ impl<T: Eq + Hash + Clone + 'static> Interner<T> {

pub fn intern(&self, val: T) -> Name {
let mut map = self.map.borrow_mut();
match (*map).get(&val) {
Some(&idx) => return idx,
None => (),
if let Some(&idx) = (*map).get(&val) {
return idx;
}

let mut vect = self.vect.borrow_mut();
Expand Down Expand Up @@ -161,9 +160,8 @@ impl StrInterner {

pub fn intern(&self, val: &str) -> Name {
let mut map = self.map.borrow_mut();
match map.get(val) {
Some(&idx) => return idx,
None => (),
if let Some(&idx) = map.get(val) {
return idx;
}

let new_idx = Name(self.len() as u32);
Expand Down