diff --git a/src/compiletest/runtest.rs b/src/compiletest/runtest.rs index 55f158675321..8ae363931829 100644 --- a/src/compiletest/runtest.rs +++ b/src/compiletest/runtest.rs @@ -864,7 +864,7 @@ fn check_debugger_output(debugger_run_result: &ProcRes, check_lines: &[String]) } first = false; } - if !failed && rest.len() == 0 { + if !failed && rest.is_empty() { i += 1; } if i == num_check_lines { @@ -1662,7 +1662,7 @@ fn _arm_push_aux_shared_library(config: &Config, testfile: &Path) { // codegen tests (vs. clang) fn append_suffix_to_stem(p: &Path, suffix: &str) -> PathBuf { - if suffix.len() == 0 { + if suffix.is_empty() { p.to_path_buf() } else { let mut stem = p.file_stem().unwrap().to_os_string(); diff --git a/src/doc/reference.md b/src/doc/reference.md index cc90a69fd2ae..0ed23dae9b55 100644 --- a/src/doc/reference.md +++ b/src/doc/reference.md @@ -3788,7 +3788,7 @@ its type parameters are types: ```ignore fn map(f: |A| -> B, xs: &[A]) -> Vec { - if xs.len() == 0 { + if xs.is_empty() { return vec![]; } let first: B = f(xs[0].clone()); diff --git a/src/libcollections/btree/map.rs b/src/libcollections/btree/map.rs index 413100039a2c..859d5ea99bf5 100644 --- a/src/libcollections/btree/map.rs +++ b/src/libcollections/btree/map.rs @@ -692,7 +692,7 @@ mod stack { // We've reached the root, so no matter what, we're done. We manually // access the root via the tree itself to avoid creating any dangling // pointers. - if self.map.root.len() == 0 && !self.map.root.is_leaf() { + if self.map.root.is_empty() && !self.map.root.is_leaf() { // We've emptied out the root, so make its only child the new root. // If it's a leaf, we just let it become empty. self.map.depth -= 1; diff --git a/src/libcollections/btree/node.rs b/src/libcollections/btree/node.rs index 26c57256049c..7f269c423f10 100644 --- a/src/libcollections/btree/node.rs +++ b/src/libcollections/btree/node.rs @@ -1097,7 +1097,7 @@ impl Node { /// When a node has no keys or values and only a single edge, extract that edge. pub fn hoist_lone_child(&mut self) { // Necessary for correctness, but in a private module - debug_assert!(self.len() == 0); + debug_assert!(self.is_empty()); debug_assert!(!self.is_leaf()); unsafe { diff --git a/src/libcore/slice.rs b/src/libcore/slice.rs index 0e6acf0160d8..4b1742a43482 100644 --- a/src/libcore/slice.rs +++ b/src/libcore/slice.rs @@ -204,7 +204,7 @@ impl SliceExt for [T] { #[inline] fn first(&self) -> Option<&T> { - if self.len() == 0 { None } else { Some(&self[0]) } + if self.is_empty() { None } else { Some(&self[0]) } } #[inline] @@ -217,7 +217,7 @@ impl SliceExt for [T] { #[inline] fn last(&self) -> Option<&T> { - if self.len() == 0 { None } else { Some(&self[self.len() - 1]) } + if self.is_empty() { None } else { Some(&self[self.len() - 1]) } } #[inline] @@ -296,7 +296,7 @@ impl SliceExt for [T] { #[inline] fn first_mut(&mut self) -> Option<&mut T> { - if self.len() == 0 { None } else { Some(&mut self[0]) } + if self.is_empty() { None } else { Some(&mut self[0]) } } #[inline] @@ -1306,7 +1306,7 @@ impl<'a, T> Iterator for Chunks<'a, T> { #[inline] fn next(&mut self) -> Option<&'a [T]> { - if self.v.len() == 0 { + if self.v.is_empty() { None } else { let chunksz = cmp::min(self.v.len(), self.size); @@ -1318,7 +1318,7 @@ impl<'a, T> Iterator for Chunks<'a, T> { #[inline] fn size_hint(&self) -> (usize, Option) { - if self.v.len() == 0 { + if self.v.is_empty() { (0, Some(0)) } else { let n = self.v.len() / self.size; @@ -1333,7 +1333,7 @@ impl<'a, T> Iterator for Chunks<'a, T> { impl<'a, T> DoubleEndedIterator for Chunks<'a, T> { #[inline] fn next_back(&mut self) -> Option<&'a [T]> { - if self.v.len() == 0 { + if self.v.is_empty() { None } else { let remainder = self.v.len() % self.size; @@ -1384,7 +1384,7 @@ impl<'a, T> Iterator for ChunksMut<'a, T> { #[inline] fn next(&mut self) -> Option<&'a mut [T]> { - if self.v.len() == 0 { + if self.v.is_empty() { None } else { let sz = cmp::min(self.v.len(), self.chunk_size); @@ -1397,7 +1397,7 @@ impl<'a, T> Iterator for ChunksMut<'a, T> { #[inline] fn size_hint(&self) -> (usize, Option) { - if self.v.len() == 0 { + if self.v.is_empty() { (0, Some(0)) } else { let n = self.v.len() / self.chunk_size; @@ -1412,7 +1412,7 @@ impl<'a, T> Iterator for ChunksMut<'a, T> { impl<'a, T> DoubleEndedIterator for ChunksMut<'a, T> { #[inline] fn next_back(&mut self) -> Option<&'a mut [T]> { - if self.v.len() == 0 { + if self.v.is_empty() { None } else { let remainder = self.v.len() % self.chunk_size; diff --git a/src/libcore/str/mod.rs b/src/libcore/str/mod.rs index fc623f21167c..2d6ef39361e8 100644 --- a/src/libcore/str/mod.rs +++ b/src/libcore/str/mod.rs @@ -1119,7 +1119,7 @@ enum OldSearcher { impl OldSearcher { #[allow(dead_code)] fn new(haystack: &[u8], needle: &[u8]) -> OldSearcher { - if needle.len() == 0 { + if needle.is_empty() { // Handle specially unimplemented!() // FIXME: Tune this. diff --git a/src/libcore/str/pattern.rs b/src/libcore/str/pattern.rs index 62b693dcbe6a..9a96612195cf 100644 --- a/src/libcore/str/pattern.rs +++ b/src/libcore/str/pattern.rs @@ -457,7 +457,7 @@ fn str_search_step(mut m: &mut StrSearcher, { if m.state.done() { SearchStep::Done - } else if m.needle.len() == 0 && m.start <= m.end { + } else if m.needle.is_empty() && m.start <= m.end { // Case for needle == "" if let State::Reject(a, b) = m.state.take() { SearchStep::Reject(a, b) diff --git a/src/liblog/directive.rs b/src/liblog/directive.rs index 46b9b2ed8653..9ea680c7efe7 100644 --- a/src/liblog/directive.rs +++ b/src/liblog/directive.rs @@ -45,7 +45,7 @@ pub fn parse_logging_spec(spec: &str) -> (Vec, Option) { return (dirs, None); } mods.map(|m| { for s in m.split(',') { - if s.len() == 0 { continue } + if s.is_empty() { continue } let mut parts = s.split('='); let (log_level, name) = match (parts.next(), parts.next().map(|s| s.trim()), parts.next()) { (Some(part0), None, None) => { diff --git a/src/librustc/metadata/creader.rs b/src/librustc/metadata/creader.rs index a2028c5ae722..802c5815398f 100644 --- a/src/librustc/metadata/creader.rs +++ b/src/librustc/metadata/creader.rs @@ -80,7 +80,7 @@ pub fn validate_crate_name(sess: Option<&Session>, s: &str, sp: Option) { (None, Some(sess)) => sess.err(s), } }; - if s.len() == 0 { + if s.is_empty() { say("crate name must not be empty"); } for c in s.chars() { diff --git a/src/librustc/metadata/decoder.rs b/src/librustc/metadata/decoder.rs index a659a93aef30..6b3bde409f54 100644 --- a/src/librustc/metadata/decoder.rs +++ b/src/librustc/metadata/decoder.rs @@ -767,7 +767,7 @@ pub fn get_enum_variants<'tcx>(intr: Rc, cdata: Cmd, id: ast::Nod get_type(cdata, field_ty.id.node, tcx).ty }) .collect(); - let arg_names = if arg_names.len() == 0 { None } else { Some(arg_names) }; + let arg_names = if arg_names.is_empty() { None } else { Some(arg_names) }; (None, arg_tys, arg_names) } @@ -1383,7 +1383,7 @@ pub fn get_dylib_dependency_formats(cdata: Cmd) debug!("found dylib deps: {}", formats.as_str_slice()); for spec in formats.as_str_slice().split(',') { - if spec.len() == 0 { continue } + if spec.is_empty() { continue } let cnum = spec.split(':').nth(0).unwrap(); let link = spec.split(':').nth(1).unwrap(); let cnum: ast::CrateNum = cnum.parse().unwrap(); diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs index f9d3d707bb5d..50ad8526e8c5 100644 --- a/src/librustc/metadata/encoder.rs +++ b/src/librustc/metadata/encoder.rs @@ -1751,7 +1751,7 @@ fn encode_codemap(ecx: &EncodeContext, rbml_w: &mut Encoder) { for filemap in &codemap.files.borrow()[..] { - if filemap.lines.borrow().len() == 0 || filemap.is_imported() { + if filemap.lines.borrow().is_empty() || filemap.is_imported() { // No need to export empty filemaps, as they can't contain spans // that need translation. // Also no need to re-export imported filemaps, as any downstream diff --git a/src/librustc/metadata/loader.rs b/src/librustc/metadata/loader.rs index 7b63e38b5859..97b1dae7223b 100644 --- a/src/librustc/metadata/loader.rs +++ b/src/librustc/metadata/loader.rs @@ -517,7 +517,7 @@ impl<'a> Context<'a> { // library's metadata sections. In theory we should // read both, but reading dylib metadata is quite // slow. - if m.len() == 0 { + if m.is_empty() { return None } else if m.len() == 1 { return Some(m.into_iter().next().unwrap()) diff --git a/src/librustc/middle/check_match.rs b/src/librustc/middle/check_match.rs index 14df040fb79e..912854a6d7df 100644 --- a/src/librustc/middle/check_match.rs +++ b/src/librustc/middle/check_match.rs @@ -239,7 +239,7 @@ fn check_for_bindings_named_the_same_as_variants(cx: &MatchCheckCtxt, pat: &Pat) if let Some(DefLocal(_)) = def { if ty::enum_variants(cx.tcx, def_id).iter().any(|variant| token::get_name(variant.name) == token::get_name(ident.node.name) - && variant.args.len() == 0 + && variant.args.is_empty() ) { span_warn!(cx.tcx.sess, p.span, E0170, "pattern binding `{}` is named the same as one \ @@ -636,19 +636,19 @@ fn is_useful(cx: &MatchCheckCtxt, -> Usefulness { let &Matrix(ref rows) = matrix; debug!("{:?}", matrix); - if rows.len() == 0 { + if rows.is_empty() { return match witness { ConstructWitness => UsefulWithWitness(vec!()), LeaveOutWitness => Useful }; } - if rows[0].len() == 0 { + if rows[0].is_empty() { return NotUseful; } assert!(rows.iter().all(|r| r.len() == v.len())); let real_pat = match rows.iter().find(|r| (*r)[0].id != DUMMY_NODE_ID) { Some(r) => raw_pat(r[0]), - None if v.len() == 0 => return NotUseful, + None if v.is_empty() => return NotUseful, None => v[0] }; let left_ty = if real_pat.id == DUMMY_NODE_ID { diff --git a/src/librustc/middle/infer/error_reporting.rs b/src/librustc/middle/infer/error_reporting.rs index 03e76f5ee257..89af7f072d71 100644 --- a/src/librustc/middle/infer/error_reporting.rs +++ b/src/librustc/middle/infer/error_reporting.rs @@ -1241,7 +1241,7 @@ impl<'a, 'tcx> Rebuilder<'a, 'tcx> { let lifetimes = path.segments.last().unwrap().parameters.lifetimes(); let mut insert = Vec::new(); - if lifetimes.len() == 0 { + if lifetimes.is_empty() { let anon = self.cur_anon.get(); for (i, a) in (anon..anon+expected).enumerate() { if anon_nums.contains(&a) { @@ -1361,7 +1361,7 @@ impl<'a, 'tcx> Rebuilder<'a, 'tcx> { ast::AngleBracketedParameters(ref data) => { let mut new_lts = Vec::new(); - if data.lifetimes.len() == 0 { + if data.lifetimes.is_empty() { // traverse once to see if there's a need to insert lifetime let need_insert = (0..expected).any(|i| { indexes.contains(&i) diff --git a/src/librustc/middle/infer/region_inference/graphviz.rs b/src/librustc/middle/infer/region_inference/graphviz.rs index 1fcbf80c904e..054cec68745a 100644 --- a/src/librustc/middle/infer/region_inference/graphviz.rs +++ b/src/librustc/middle/infer/region_inference/graphviz.rs @@ -88,7 +88,7 @@ pub fn maybe_print_constraints_for<'a, 'tcx>(region_vars: &RegionVarBindings<'a, Err(_) => "/tmp/constraints.node%.dot".to_string(), }; - if output_template.len() == 0 { + if output_template.is_empty() { tcx.sess.bug("empty string provided as RUST_REGION_GRAPH"); } diff --git a/src/librustc/middle/liveness.rs b/src/librustc/middle/liveness.rs index 786cd902c53c..8d9ddfb3d5d5 100644 --- a/src/librustc/middle/liveness.rs +++ b/src/librustc/middle/liveness.rs @@ -716,7 +716,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> { None => { // Vanilla 'break' or 'loop', so use the enclosing // loop scope - if self.loop_scope.len() == 0 { + if self.loop_scope.is_empty() { self.ir.tcx.sess.span_bug(sp, "break outside loop"); } else { *self.loop_scope.last().unwrap() @@ -1586,7 +1586,7 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> { fn should_warn(&self, var: Variable) -> Option { let name = self.ir.variable_name(var); - if name.len() == 0 || name.as_bytes()[0] == ('_' as u8) { + if name.is_empty() || name.as_bytes()[0] == ('_' as u8) { None } else { Some(name) diff --git a/src/librustc/middle/subst.rs b/src/librustc/middle/subst.rs index e2ebe2bc0f1e..d9cdf0fa1cb3 100644 --- a/src/librustc/middle/subst.rs +++ b/src/librustc/middle/subst.rs @@ -361,7 +361,7 @@ impl VecPerParamSpace { pub fn get_self<'a>(&'a self) -> Option<&'a T> { let v = self.get_slice(SelfSpace); assert!(v.len() <= 1); - if v.len() == 0 { None } else { Some(&v[0]) } + if v.is_empty() { None } else { Some(&v[0]) } } pub fn len(&self, space: ParamSpace) -> usize { diff --git a/src/librustc/middle/traits/fulfill.rs b/src/librustc/middle/traits/fulfill.rs index ffd3299175de..5938c6df92a6 100644 --- a/src/librustc/middle/traits/fulfill.rs +++ b/src/librustc/middle/traits/fulfill.rs @@ -298,7 +298,7 @@ impl<'tcx> FulfillmentContext<'tcx> { self.predicates.len(), errors.len()); - if errors.len() == 0 { + if errors.is_empty() { Ok(()) } else { Err(errors) diff --git a/src/librustc/middle/traits/select.rs b/src/librustc/middle/traits/select.rs index 08357084bb20..ed8a6fb0200a 100644 --- a/src/librustc/middle/traits/select.rs +++ b/src/librustc/middle/traits/select.rs @@ -698,7 +698,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { // is checked for in `evaluate_stack` (and hence users // who might care about this case, like coherence, should use // that function). - if candidates.len() == 0 { + if candidates.is_empty() { return Err(Unimplemented); } @@ -873,7 +873,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> { try!(self.assemble_candidates_from_caller_bounds(stack, &mut candidates)); // Default implementations have lower priority, so we only // consider triggering a default if there is no other impl that can apply. - if candidates.vec.len() == 0 { + if candidates.vec.is_empty() { try!(self.assemble_candidates_from_default_impls(obligation, &mut candidates)); } debug!("candidate list size: {}", candidates.vec.len()); diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs index be126b0b54c8..b5b148e491b3 100644 --- a/src/librustc/middle/ty.rs +++ b/src/librustc/middle/ty.rs @@ -3036,7 +3036,7 @@ pub fn mk_trait<'tcx>(cx: &ctxt<'tcx>, } fn bound_list_is_sorted(bounds: &[ty::PolyProjectionPredicate]) -> bool { - bounds.len() == 0 || + bounds.is_empty() || bounds[1..].iter().enumerate().all( |(index, bound)| bounds[index].sort_key() <= bound.sort_key()) } @@ -3687,7 +3687,7 @@ pub fn type_contents<'tcx>(cx: &ctxt<'tcx>, ty: Ty<'tcx>) -> TypeContents { if variants.len() == 2 { let mut data_idx = 0; - if variants[0].args.len() == 0 { + if variants[0].args.is_empty() { data_idx = 1; } @@ -4200,10 +4200,10 @@ pub fn type_is_c_like_enum(cx: &ctxt, ty: Ty) -> bool { match ty.sty { ty_enum(did, _) => { let variants = enum_variants(cx, did); - if variants.len() == 0 { + if variants.is_empty() { false } else { - variants.iter().all(|v| v.args.len() == 0) + variants.iter().all(|v| v.args.is_empty()) } } _ => false diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs index a7d608d2c879..3fb6c191f6ce 100644 --- a/src/librustc/session/config.rs +++ b/src/librustc/session/config.rs @@ -902,7 +902,7 @@ pub fn build_session_options(matches: &getopts::Matches) -> Options { }; output_types.sort(); output_types.dedup(); - if output_types.len() == 0 { + if output_types.is_empty() { output_types.push(OutputTypeExe); } diff --git a/src/librustc/util/ppaux.rs b/src/librustc/util/ppaux.rs index 7358b4cc0f6e..e6f1c76b2e47 100644 --- a/src/librustc/util/ppaux.rs +++ b/src/librustc/util/ppaux.rs @@ -1269,7 +1269,7 @@ impl<'tcx, T> UserString<'tcx> for ty::Binder let names: Vec<_> = names.iter().map(|s| &s[..]).collect(); let value_str = unbound_value.user_string(tcx); - if names.len() == 0 { + if names.is_empty() { value_str } else { format!("for<{}> {}", names.connect(","), value_str) diff --git a/src/librustc_driver/driver.rs b/src/librustc_driver/driver.rs index e310798b20ab..1453c9b784b6 100644 --- a/src/librustc_driver/driver.rs +++ b/src/librustc_driver/driver.rs @@ -887,9 +887,9 @@ pub fn collect_crate_types(session: &Session, // command line, then reuse the empty `base` Vec to hold the types that // will be found in crate attributes. let mut base = session.opts.crate_types.clone(); - if base.len() == 0 { + if base.is_empty() { base.extend(attr_types.into_iter()); - if base.len() == 0 { + if base.is_empty() { base.push(link::default_output_for_target(session)); } base.sort(); diff --git a/src/librustc_driver/lib.rs b/src/librustc_driver/lib.rs index 89c19cfb0b02..8f21a800d5c4 100644 --- a/src/librustc_driver/lib.rs +++ b/src/librustc_driver/lib.rs @@ -425,7 +425,7 @@ impl RustcDefaultCalls { odir: &Option, ofile: &Option) -> Compilation { - if sess.opts.prints.len() == 0 { + if sess.opts.prints.is_empty() { return Compilation::Continue; } diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs index 410f31e0900c..00c3450ebb93 100644 --- a/src/librustc_driver/pretty.rs +++ b/src/librustc_driver/pretty.rs @@ -676,7 +676,7 @@ fn print_flowgraph(variants: Vec, }; match code { - _ if variants.len() == 0 => { + _ if variants.is_empty() => { let r = dot::render(&lcfg, &mut out); return expand_err_details(r); } diff --git a/src/librustc_resolve/build_reduced_graph.rs b/src/librustc_resolve/build_reduced_graph.rs index 52db6013f4d5..777154f3c9c3 100644 --- a/src/librustc_resolve/build_reduced_graph.rs +++ b/src/librustc_resolve/build_reduced_graph.rs @@ -767,7 +767,7 @@ impl<'a, 'b:'a, 'tcx:'b> GraphBuilder<'a, 'b, 'tcx> { f.name }).collect::>(); - if fields.len() == 0 { + if fields.is_empty() { child_name_bindings.define_value(def, DUMMY_SP, modifiers); } diff --git a/src/librustc_resolve/lib.rs b/src/librustc_resolve/lib.rs index 6fd59a205323..1b6af605fb07 100644 --- a/src/librustc_resolve/lib.rs +++ b/src/librustc_resolve/lib.rs @@ -2172,7 +2172,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> { // check that all of the arms in an or-pattern have exactly the // same set of bindings, with the same binding modes for each. fn check_consistent_bindings(&mut self, arm: &Arm) { - if arm.pats.len() == 0 { + if arm.pats.is_empty() { return } let map_0 = self.binding_mode_map(&*arm.pats[0]); @@ -3522,7 +3522,7 @@ fn module_to_string(module: &Module) -> String { } collect_mod(&mut names, module); - if names.len() == 0 { + if names.is_empty() { return "???".to_string(); } names_to_string(&names.into_iter().rev().collect::>()) diff --git a/src/librustc_resolve/resolve_imports.rs b/src/librustc_resolve/resolve_imports.rs index f1a8507b1781..4b488981bfbc 100644 --- a/src/librustc_resolve/resolve_imports.rs +++ b/src/librustc_resolve/resolve_imports.rs @@ -304,7 +304,7 @@ impl<'a, 'b:'a, 'tcx:'b> ImportResolver<'a, 'b, 'tcx> { module_to_string(&*module_)); // First, resolve the module path for the directive, if necessary. - let container = if module_path.len() == 0 { + let container = if module_path.is_empty() { // Use the crate root. Some((self.resolver.graph_root.get_module(), LastMod(AllPublic))) } else { diff --git a/src/librustc_trans/back/link.rs b/src/librustc_trans/back/link.rs index ad7773518989..33fadf804f5a 100644 --- a/src/librustc_trans/back/link.rs +++ b/src/librustc_trans/back/link.rs @@ -463,7 +463,7 @@ pub fn filename_for_input(sess: &Session, } config::CrateTypeExecutable => { let suffix = &sess.target.target.options.exe_suffix; - if suffix.len() == 0 { + if suffix.is_empty() { out_filename.to_path_buf() } else { out_filename.with_extension(&suffix[1..]) diff --git a/src/librustc_trans/save/mod.rs b/src/librustc_trans/save/mod.rs index 1a19d4a1e454..21c95f4ce4ad 100644 --- a/src/librustc_trans/save/mod.rs +++ b/src/librustc_trans/save/mod.rs @@ -263,7 +263,7 @@ impl <'l, 'tcx> DxrVisitor<'l, 'tcx> { fn process_formals(&mut self, formals: &Vec, qualname: &str) { for arg in formals { - assert!(self.collected_paths.len() == 0 && !self.collecting); + assert!(self.collected_paths.is_empty() && !self.collecting); self.collecting = true; self.visit_pat(&*arg.pat); self.collecting = false; @@ -1394,7 +1394,7 @@ impl<'l, 'tcx, 'v> Visitor<'v> for DxrVisitor<'l, 'tcx> { } fn visit_arm(&mut self, arm: &ast::Arm) { - assert!(self.collected_paths.len() == 0 && !self.collecting); + assert!(self.collected_paths.is_empty() && !self.collecting); self.collecting = true; for pattern in &arm.pats { // collect paths from the arm's patterns @@ -1462,7 +1462,7 @@ impl<'l, 'tcx, 'v> Visitor<'v> for DxrVisitor<'l, 'tcx> { // The local could declare multiple new vars, we must walk the // pattern and collect them all. - assert!(self.collected_paths.len() == 0 && !self.collecting); + assert!(self.collected_paths.is_empty() && !self.collecting); self.collecting = true; self.visit_pat(&*l.pat); self.collecting = false; diff --git a/src/librustc_trans/trans/_match.rs b/src/librustc_trans/trans/_match.rs index 390a9cc4d26d..54afeca13edd 100644 --- a/src/librustc_trans/trans/_match.rs +++ b/src/librustc_trans/trans/_match.rs @@ -988,7 +988,7 @@ fn compile_submatch<'a, 'p, 'blk, 'tcx>(bcx: Block<'blk, 'tcx>, let _indenter = indenter(); let _icx = push_ctxt("match::compile_submatch"); let mut bcx = bcx; - if m.len() == 0 { + if m.is_empty() { if chk.is_fallible() { chk.handle_fail(bcx); } @@ -1152,7 +1152,7 @@ fn compile_submatch_continue<'a, 'p, 'blk, 'tcx>(mut bcx: Block<'blk, 'tcx>, }; let defaults = enter_default(else_cx, dm, m, col, val); - let exhaustive = chk.is_infallible() && defaults.len() == 0; + let exhaustive = chk.is_infallible() && defaults.is_empty(); let len = opts.len(); // Compile subtrees for each option diff --git a/src/librustc_trans/trans/adt.rs b/src/librustc_trans/trans/adt.rs index fd1fff308dfe..f574b4ed8db9 100644 --- a/src/librustc_trans/trans/adt.rs +++ b/src/librustc_trans/trans/adt.rs @@ -235,7 +235,7 @@ fn represent_type_uncached<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, let dtor = ty::ty_dtor(cx.tcx(), def_id).has_drop_flag(); - if cases.len() == 0 { + if cases.is_empty() { // Uninhabitable; represent as unit // (Typechecking will reject discriminant-sizing attrs.) assert_eq!(hint, attr::ReprAny); @@ -244,7 +244,7 @@ fn represent_type_uncached<'a, 'tcx>(cx: &CrateContext<'a, 'tcx>, dtor_to_init_u8(dtor)); } - if !dtor && cases.iter().all(|c| c.tys.len() == 0) { + if !dtor && cases.iter().all(|c| c.tys.is_empty()) { // All bodies empty -> intlike let discrs: Vec = cases.iter().map(|c| c.discr).collect(); let bounds = IntBounds { diff --git a/src/librustc_trans/trans/cabi_x86_64.rs b/src/librustc_trans/trans/cabi_x86_64.rs index 754b7ee5cf55..8d946e2743bd 100644 --- a/src/librustc_trans/trans/cabi_x86_64.rs +++ b/src/librustc_trans/trans/cabi_x86_64.rs @@ -70,7 +70,7 @@ trait ClassList { impl ClassList for [RegClass] { fn is_pass_byval(&self) -> bool { - if self.len() == 0 { return false; } + if self.is_empty() { return false; } let class = self[0]; class == Memory @@ -79,7 +79,7 @@ impl ClassList for [RegClass] { } fn is_ret_bysret(&self) -> bool { - if self.len() == 0 { return false; } + if self.is_empty() { return false; } self[0] == Memory } diff --git a/src/librustc_trans/trans/debuginfo.rs b/src/librustc_trans/trans/debuginfo.rs index 3e6e6b499854..40cbb909fc15 100644 --- a/src/librustc_trans/trans/debuginfo.rs +++ b/src/librustc_trans/trans/debuginfo.rs @@ -2017,7 +2017,7 @@ struct StructMemberDescriptionFactory<'tcx> { impl<'tcx> StructMemberDescriptionFactory<'tcx> { fn create_member_descriptions<'a>(&self, cx: &CrateContext<'a, 'tcx>) -> Vec { - if self.fields.len() == 0 { + if self.fields.is_empty() { return Vec::new(); } @@ -2210,7 +2210,7 @@ impl<'tcx> EnumMemberDescriptionFactory<'tcx> { adt::Univariant(ref struct_def, _) => { assert!(self.variants.len() <= 1); - if self.variants.len() == 0 { + if self.variants.is_empty() { vec![] } else { let (variant_type_metadata, diff --git a/src/librustc_trans/trans/meth.rs b/src/librustc_trans/trans/meth.rs index e2f965a95fff..e346fb0d9318 100644 --- a/src/librustc_trans/trans/meth.rs +++ b/src/librustc_trans/trans/meth.rs @@ -83,7 +83,7 @@ pub fn trans_impl(ccx: &CrateContext, for impl_item in impl_items { match impl_item.node { ast::MethodImplItem(ref sig, ref body) => { - if sig.generics.ty_params.len() == 0 { + if sig.generics.ty_params.is_empty() { let trans_everywhere = attr::requests_inline(&impl_item.attrs); for (ref ccx, is_origin) in ccx.maybe_iter(trans_everywhere) { let llfn = get_item_val(ccx, impl_item.id); diff --git a/src/librustc_trans/trans/type_of.rs b/src/librustc_trans/trans/type_of.rs index 8257dab20fac..b3ab58e416f7 100644 --- a/src/librustc_trans/trans/type_of.rs +++ b/src/librustc_trans/trans/type_of.rs @@ -69,7 +69,7 @@ pub fn untuple_arguments_if_necessary<'a, 'tcx>(ccx: &CrateContext<'a, 'tcx>, return inputs.iter().cloned().collect() } - if inputs.len() == 0 { + if inputs.is_empty() { return Vec::new() } diff --git a/src/librustc_typeck/astconv.rs b/src/librustc_typeck/astconv.rs index ff22127fdc61..6d4b660f30d9 100644 --- a/src/librustc_typeck/astconv.rs +++ b/src/librustc_typeck/astconv.rs @@ -1125,7 +1125,7 @@ fn one_bound_for_assoc_type<'tcx>(tcx: &ty::ctxt<'tcx>, span: Span) -> Result, ErrorReported> { - if bounds.len() == 0 { + if bounds.is_empty() { span_err!(tcx.sess, span, E0220, "associated type `{}` not found for `{}`", assoc_name, @@ -2042,7 +2042,7 @@ fn compute_object_lifetime_bound<'tcx>( // If there are no derived region bounds, then report back that we // can find no region bound. - if derived_region_bounds.len() == 0 { + if derived_region_bounds.is_empty() { match rscope.object_lifetime_default(span) { Some(r) => { return r; } None => { diff --git a/src/librustc_typeck/check/_match.rs b/src/librustc_typeck/check/_match.rs index 8f1a67723cb7..0959f9d1b915 100644 --- a/src/librustc_typeck/check/_match.rs +++ b/src/librustc_typeck/check/_match.rs @@ -594,7 +594,7 @@ pub fn check_pat_enum<'a, 'tcx>(pcx: &pat_ctxt<'a, 'tcx>, for (subpat, arg_ty) in subpats.iter().zip(arg_tys.iter()) { check_pat(pcx, &**subpat, *arg_ty); } - } else if arg_tys.len() == 0 { + } else if arg_tys.is_empty() { span_err!(tcx.sess, pat.span, E0024, "this pattern has {} field{}, but the corresponding {} has no fields", subpats.len(), if subpats.len() == 1 {""} else {"s"}, kind_name); diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs index 8264647b2561..ded9b86e2352 100644 --- a/src/librustc_typeck/check/mod.rs +++ b/src/librustc_typeck/check/mod.rs @@ -4719,7 +4719,7 @@ pub fn check_bounds_are_used<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, tps.len(), ppaux::ty_to_string(ccx.tcx, ty)); // make a vector of booleans initially false, set to true when used - if tps.len() == 0 { return; } + if tps.is_empty() { return; } let mut tps_used: Vec<_> = repeat(false).take(tps.len()).collect(); ty::walk_ty(ty, |t| { diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs index 51d0c18872dc..b0c994f7f640 100644 --- a/src/librustc_typeck/coherence/mod.rs +++ b/src/librustc_typeck/coherence/mod.rs @@ -387,7 +387,7 @@ impl<'a, 'tcx> CoherenceChecker<'a, 'tcx> { for &impl_did in &*trait_impls.borrow() { let items = impl_items.get(&impl_did).unwrap(); - if items.len() < 1 { + if items.is_empty() { // We'll error out later. For now, just don't ICE. continue; } diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs index 95b943b25478..aa4052253667 100644 --- a/src/librustc_typeck/collect.rs +++ b/src/librustc_typeck/collect.rs @@ -1035,7 +1035,7 @@ fn convert_struct<'a, 'tcx>(ccx: &CrateCtxt<'a, 'tcx>, match struct_def.ctor_id { None => {} Some(ctor_id) => { - if struct_def.fields.len() == 0 { + if struct_def.fields.is_empty() { // Enum-like. write_ty_to_tcx(tcx, ctor_id, selfty); @@ -1893,7 +1893,7 @@ fn compute_object_lifetime_default<'a,'tcx>(ccx: &CrateCtxt<'a,'tcx>, .flat_map(|predicate| { match *predicate { ast::WherePredicate::BoundPredicate(ref data) => { - if data.bound_lifetimes.len() == 0 && + if data.bound_lifetimes.is_empty() && is_param(ccx.tcx, &data.bounded_ty, param_id) { from_bounds(ccx, &data.bounds).into_iter() diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs index 38df0339e425..ff364eb69a83 100644 --- a/src/librustdoc/clean/mod.rs +++ b/src/librustdoc/clean/mod.rs @@ -1820,7 +1820,7 @@ impl<'tcx> Clean for ty::VariantInfo<'tcx> { fn clean(&self, cx: &DocContext) -> Item { // use syntax::parse::token::special_idents::unnamed_field; let kind = match self.arg_names.as_ref().map(|s| &**s) { - None | Some([]) if self.args.len() == 0 => CLikeVariant, + None | Some([]) if self.args.is_empty() => CLikeVariant, None | Some([]) => { TupleVariant(self.args.clean(cx)) } @@ -1874,7 +1874,7 @@ impl Clean for ast::VariantKind { fn clean(&self, cx: &DocContext) -> VariantKind { match self { &ast::TupleVariantKind(ref args) => { - if args.len() == 0 { + if args.is_empty() { CLikeVariant } else { TupleVariant(args.iter().map(|x| x.ty.clean(cx)).collect()) diff --git a/src/librustdoc/html/format.rs b/src/librustdoc/html/format.rs index f6215dcb00c5..5aded0215e9e 100644 --- a/src/librustdoc/html/format.rs +++ b/src/librustdoc/html/format.rs @@ -94,7 +94,7 @@ impl<'a> fmt::Display for TyParamBounds<'a> { impl fmt::Display for clean::Generics { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - if self.lifetimes.len() == 0 && self.type_params.len() == 0 { return Ok(()) } + if self.lifetimes.is_empty() && self.type_params.is_empty() { return Ok(()) } try!(f.write_str("<")); for (i, life) in self.lifetimes.iter().enumerate() { @@ -132,7 +132,7 @@ impl fmt::Display for clean::Generics { impl<'a> fmt::Display for WhereClause<'a> { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { let &WhereClause(gens) = self; - if gens.where_predicates.len() == 0 { + if gens.where_predicates.is_empty() { return Ok(()); } try!(f.write_str(" where ")); diff --git a/src/librustdoc/html/layout.rs b/src/librustdoc/html/layout.rs index 3acd17dedd59..a53884ca047d 100644 --- a/src/librustdoc/html/layout.rs +++ b/src/librustdoc/html/layout.rs @@ -130,7 +130,7 @@ r##" content = *t, root_path = page.root_path, ty = page.ty, - logo = if layout.logo.len() == 0 { + logo = if layout.logo.is_empty() { "".to_string() } else { format!("\ @@ -141,7 +141,7 @@ r##" title = page.title, description = page.description, keywords = page.keywords, - favicon = if layout.favicon.len() == 0 { + favicon = if layout.favicon.is_empty() { "".to_string() } else { format!(r#""#, layout.favicon) @@ -152,7 +152,7 @@ r##" sidebar = *sidebar, krate = layout.krate, play_url = layout.playground_url, - play_js = if layout.playground_url.len() == 0 { + play_js = if layout.playground_url.is_empty() { "".to_string() } else { format!(r#""#, page.root_path) diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs index cb80d071ce47..334f05fb36fa 100644 --- a/src/librustdoc/html/markdown.rs +++ b/src/librustdoc/html/markdown.rs @@ -305,7 +305,7 @@ pub fn render(w: &mut fmt::Formatter, s: &str, print_toc: bool) -> fmt::Result { let text = format!(r##"{sec}{}"##, s, lvl = level, id = id, - sec = if sec.len() == 0 { + sec = if sec.is_empty() { sec.to_string() } else { format!("{} ", sec) @@ -491,7 +491,7 @@ impl<'a> fmt::Display for Markdown<'a> { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { let Markdown(md) = *self; // This is actually common enough to special-case - if md.len() == 0 { return Ok(()) } + if md.is_empty() { return Ok(()) } render(fmt, md, false) } } diff --git a/src/librustdoc/html/render.rs b/src/librustdoc/html/render.rs index 8e33a9bd80ba..5ee78bf836ee 100644 --- a/src/librustdoc/html/render.rs +++ b/src/librustdoc/html/render.rs @@ -912,7 +912,7 @@ impl DocFolder for Cache { false) } clean::MethodItem(..) => { - if self.parent_stack.len() == 0 { + if self.parent_stack.is_empty() { ((None, None), false) } else { let last = self.parent_stack.last().unwrap(); @@ -1115,7 +1115,7 @@ impl Context { fn recurse(&mut self, s: String, f: F) -> T where F: FnOnce(&mut Context) -> T, { - if s.len() == 0 { + if s.is_empty() { panic!("Unexpected empty destination: {:?}", self.current); } let prev = self.dst.clone(); @@ -1343,7 +1343,7 @@ impl Context { fn ignore_private_item(&self, it: &clean::Item) -> bool { match it.inner { clean::ModuleItem(ref m) => { - (m.items.len() == 0 && + (m.items.is_empty() && it.doc_value().is_none() && it.visibility != Some(ast::Public)) || (self.passes.contains("strip-private") && it.visibility != Some(ast::Public)) @@ -1690,7 +1690,7 @@ struct Initializer<'a>(&'a str); impl<'a> fmt::Display for Initializer<'a> { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { let Initializer(s) = *self; - if s.len() == 0 { return Ok(()); } + if s.is_empty() { return Ok(()); } try!(write!(f, " = ")); write!(f, "{}", s) } @@ -1766,7 +1766,7 @@ fn item_trait(w: &mut fmt::Formatter, cx: &Context, it: &clean::Item, match m.inner { clean::MethodItem(_) => true, _ => false } }).collect::>(); - if t.items.len() == 0 { + if t.items.is_empty() { try!(write!(w, "{{ }}")); } else { try!(write!(w, "{{\n")); @@ -1986,7 +1986,7 @@ fn item_enum(w: &mut fmt::Formatter, it: &clean::Item, it.name.as_ref().unwrap(), e.generics, WhereClause(&e.generics))); - if e.variants.len() == 0 && !e.variants_stripped { + if e.variants.is_empty() && !e.variants_stripped { try!(write!(w, " {{}}")); } else { try!(write!(w, " {{\n")); diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs index 1393c39f66c9..008da466db01 100644 --- a/src/librustdoc/lib.rs +++ b/src/librustdoc/lib.rs @@ -219,7 +219,7 @@ pub fn main_args(args: &[String]) -> isize { return 0; } - if matches.free.len() == 0 { + if matches.free.is_empty() { println!("expected an input file to act on"); return 1; } if matches.free.len() > 1 { diff --git a/src/librustdoc/markdown.rs b/src/librustdoc/markdown.rs index 6541564d8e2b..00de4e3ec53c 100644 --- a/src/librustdoc/markdown.rs +++ b/src/librustdoc/markdown.rs @@ -74,7 +74,7 @@ pub fn render(input: &str, mut output: PathBuf, matches: &getopts::Matches, }; let (metadata, text) = extract_leading_metadata(&input_str); - if metadata.len() == 0 { + if metadata.is_empty() { let _ = writeln!(&mut io::stderr(), "invalid markdown file: expecting initial line with `% ...TITLE...`"); return 5; diff --git a/src/librustdoc/passes.rs b/src/librustdoc/passes.rs index 953b442bb3ce..7b8241e9b5ba 100644 --- a/src/librustdoc/passes.rs +++ b/src/librustdoc/passes.rs @@ -215,9 +215,9 @@ impl<'a> fold::DocFolder for Stripper<'a> { match i.inner { // emptied modules/impls have no need to exist clean::ModuleItem(ref m) - if m.items.len() == 0 && + if m.items.is_empty() && i.doc_value().is_none() => None, - clean::ImplItem(ref i) if i.items.len() == 0 => None, + clean::ImplItem(ref i) if i.items.is_empty() => None, _ => { self.retained.insert(i.def_id.node); Some(i) diff --git a/src/librustdoc/test.rs b/src/librustdoc/test.rs index 94b521a89cfb..449f9c79d1d4 100644 --- a/src/librustdoc/test.rs +++ b/src/librustdoc/test.rs @@ -409,7 +409,7 @@ impl Collector { impl DocFolder for Collector { fn fold_item(&mut self, item: clean::Item) -> Option { let pushed = match item.name { - Some(ref name) if name.len() == 0 => false, + Some(ref name) if name.is_empty() => false, Some(ref name) => { self.names.push(name.to_string()); true } None => false }; diff --git a/src/librustdoc/visit_ast.rs b/src/librustdoc/visit_ast.rs index a1fa96322a4e..e4f4dbaafbe4 100644 --- a/src/librustdoc/visit_ast.rs +++ b/src/librustdoc/visit_ast.rs @@ -175,7 +175,7 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> { please_inline) }).collect::>(); - if mine.len() == 0 { + if mine.is_empty() { None } else { Some(ast::ViewPathList(p, mine)) diff --git a/src/libserialize/json.rs b/src/libserialize/json.rs index 620ea40b48a3..8f020d0857d7 100644 --- a/src/libserialize/json.rs +++ b/src/libserialize/json.rs @@ -3837,7 +3837,7 @@ mod tests { let mut stack = Stack::new(); assert!(stack.is_empty()); - assert!(stack.len() == 0); + assert!(stack.is_empty()); assert!(!stack.last_is_index()); stack.push_index(0); diff --git a/src/libstd/collections/hash/set.rs b/src/libstd/collections/hash/set.rs index 6b0546b1ee72..62c03389b24a 100644 --- a/src/libstd/collections/hash/set.rs +++ b/src/libstd/collections/hash/set.rs @@ -430,7 +430,7 @@ impl HashSet /// assert!(!v.is_empty()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - pub fn is_empty(&self) -> bool { self.map.len() == 0 } + pub fn is_empty(&self) -> bool { self.map.is_empty() } /// Clears the set, returning all elements in an iterator. #[inline] diff --git a/src/libstd/sys/windows/process2.rs b/src/libstd/sys/windows/process2.rs index 749539219217..3d5c9867a6f9 100644 --- a/src/libstd/sys/windows/process2.rs +++ b/src/libstd/sys/windows/process2.rs @@ -381,7 +381,7 @@ fn make_command_line(prog: &OsStr, args: &[OsString]) -> Vec { // it will be dropped entirely when parsed on the other end. let arg_bytes = &arg.as_inner().inner.as_inner(); let quote = arg_bytes.iter().any(|c| *c == b' ' || *c == b'\t') - || arg_bytes.len() == 0; + || arg_bytes.is_empty(); if quote { cmd.push('"' as u16); } diff --git a/src/libsyntax/codemap.rs b/src/libsyntax/codemap.rs index 5bbf79d04773..f024a3139a61 100644 --- a/src/libsyntax/codemap.rs +++ b/src/libsyntax/codemap.rs @@ -652,7 +652,7 @@ impl CodeMap { } pub fn span_to_string(&self, sp: Span) -> String { - if self.files.borrow().len() == 0 && sp == DUMMY_SP { + if self.files.borrow().is_empty() && sp == DUMMY_SP { return "no-location".to_string(); } diff --git a/src/libsyntax/ext/deriving/generic/mod.rs b/src/libsyntax/ext/deriving/generic/mod.rs index ac96375095e1..dcfc6b675e3c 100644 --- a/src/libsyntax/ext/deriving/generic/mod.rs +++ b/src/libsyntax/ext/deriving/generic/mod.rs @@ -1248,7 +1248,7 @@ impl<'a> MethodDef<'a> { match_arms.push(catch_all_match_arm); - } else if variants.len() == 0 { + } else if variants.is_empty() { // As an additional wrinkle, For a zero-variant enum A, // currently the compiler // will accept `fn (a: &Self) { match *a { } }` diff --git a/src/libsyntax/ext/env.rs b/src/libsyntax/ext/env.rs index f72303985e78..2ca74644b3bf 100644 --- a/src/libsyntax/ext/env.rs +++ b/src/libsyntax/ext/env.rs @@ -65,7 +65,7 @@ pub fn expand_option_env<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[ast::TokenT pub fn expand_env<'cx>(cx: &'cx mut ExtCtxt, sp: Span, tts: &[ast::TokenTree]) -> Box { let mut exprs = match get_exprs_from_tts(cx, sp, tts) { - Some(ref exprs) if exprs.len() == 0 => { + Some(ref exprs) if exprs.is_empty() => { cx.span_err(sp, "env! takes 1 or 2 arguments"); return DummyResult::expr(sp); } diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs index b65798b8a498..74ec219af154 100644 --- a/src/libsyntax/ext/expand.rs +++ b/src/libsyntax/ext/expand.rs @@ -841,7 +841,7 @@ fn expand_non_macro_stmt(Spanned {node, span: stmt_span}: Stmt, fld: &mut MacroE fn expand_arm(arm: ast::Arm, fld: &mut MacroExpander) -> ast::Arm { // expand pats... they might contain macro uses: let expanded_pats = arm.pats.move_map(|pat| fld.fold_pat(pat)); - if expanded_pats.len() == 0 { + if expanded_pats.is_empty() { panic!("encountered match arm with 0 patterns"); } // all of the pats must have the same set of bindings, so use the @@ -1887,7 +1887,7 @@ mod test { let binding_name = mtwt::resolve(bindings[binding_idx]); let binding_marks = mtwt::marksof(bindings[binding_idx].ctxt, invalid_name); // shouldmatch can't name varrefs that don't exist: - assert!((shouldmatch.len() == 0) || + assert!((shouldmatch.is_empty()) || (varrefs.len() > *shouldmatch.iter().max().unwrap())); for (idx,varref) in varrefs.iter().enumerate() { let print_hygiene_debug_info = || { diff --git a/src/libsyntax/ext/tt/macro_parser.rs b/src/libsyntax/ext/tt/macro_parser.rs index 4e0b74401a26..dcbf3c2c8928 100644 --- a/src/libsyntax/ext/tt/macro_parser.rs +++ b/src/libsyntax/ext/tt/macro_parser.rs @@ -472,7 +472,7 @@ pub fn parse(sess: &ParseSess, "local ambiguity: multiple parsing options: \ built-in NTs {} or {} other options.", nts, next_eis.len()).to_string()); - } else if bb_eis.len() == 0 && next_eis.len() == 0 { + } else if bb_eis.is_empty() && next_eis.is_empty() { return Failure(sp, format!("no rules expected the token `{}`", pprust::token_to_string(&tok)).to_string()); } else if next_eis.len() > 0 { diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs index e45b7c1df91c..fe5fbdccf612 100644 --- a/src/libsyntax/parse/parser.rs +++ b/src/libsyntax/parse/parser.rs @@ -449,7 +449,7 @@ impl<'a> Parser<'a> { (format!("expected one of {}, found `{}`", expect, actual)) - } else if expected.len() == 0 { + } else if expected.is_empty() { (format!("unexpected token: `{}`", actual)) } else { @@ -1244,7 +1244,7 @@ impl<'a> Parser<'a> { // In type grammar, `+` is treated like a binary operator, // and hence both L and R side are required. - if bounds.len() == 0 { + if bounds.is_empty() { let last_span = self.last_span; self.span_err(last_span, "at least one type parameter bound \ @@ -2191,7 +2191,7 @@ impl<'a> Parser<'a> { &[token::CloseDelim(token::Brace)])); } - if fields.len() == 0 && base.is_none() { + if fields.is_empty() && base.is_none() { let last_span = self.last_span; self.span_err(last_span, "structure literal must either \ @@ -3914,7 +3914,7 @@ impl<'a> Parser<'a> { let hi = self.span.hi; let span = mk_sp(lo, hi); - if bounds.len() == 0 { + if bounds.is_empty() { self.span_err(span, "each predicate in a `where` clause must have \ at least one bound in it"); @@ -4572,7 +4572,7 @@ impl<'a> Parser<'a> { fields.push(try!(self.parse_struct_decl_field(true))); } - if fields.len() == 0 { + if fields.is_empty() { return Err(self.fatal(&format!("unit-like struct definition should be \ written as `struct {};`", token::get_ident(class_name.clone())))); @@ -4611,7 +4611,7 @@ impl<'a> Parser<'a> { Ok(spanned(lo, p.span.hi, struct_field_)) })); - if fields.len() == 0 { + if fields.is_empty() { return Err(self.fatal(&format!("unit-like struct definition should be \ written as `struct {};`", token::get_ident(class_name.clone())))); @@ -5023,7 +5023,7 @@ impl<'a> Parser<'a> { all_nullary = false; let start_span = self.span; let struct_def = try!(self.parse_struct_def()); - if struct_def.fields.len() == 0 { + if struct_def.fields.is_empty() { self.span_err(start_span, &format!("unit-like struct variant should be written \ without braces, as `{},`", diff --git a/src/libsyntax/print/pprust.rs b/src/libsyntax/print/pprust.rs index 3f883fb11725..0e9b471393bd 100644 --- a/src/libsyntax/print/pprust.rs +++ b/src/libsyntax/print/pprust.rs @@ -2546,7 +2546,7 @@ impl<'a> State<'a> { pub fn print_where_clause(&mut self, where_clause: &ast::WhereClause) -> io::Result<()> { - if where_clause.predicates.len() == 0 { + if where_clause.predicates.is_empty() { return Ok(()) } diff --git a/src/libterm/terminfo/searcher.rs b/src/libterm/terminfo/searcher.rs index 3083f8e89298..16062060df08 100644 --- a/src/libterm/terminfo/searcher.rs +++ b/src/libterm/terminfo/searcher.rs @@ -20,7 +20,7 @@ use std::path::PathBuf; /// Return path to database entry for `term` #[allow(deprecated)] pub fn get_dbpath_for_term(term: &str) -> Option> { - if term.len() == 0 { + if term.is_empty() { return None; } diff --git a/src/libunicode/u_str.rs b/src/libunicode/u_str.rs index 6852cfe11eb7..701187ed35a6 100644 --- a/src/libunicode/u_str.rs +++ b/src/libunicode/u_str.rs @@ -157,7 +157,7 @@ impl<'a> Iterator for Graphemes<'a> { #[inline] fn next(&mut self) -> Option<&'a str> { use tables::grapheme as gr; - if self.string.len() == 0 { + if self.string.is_empty() { return None; } @@ -257,7 +257,7 @@ impl<'a> DoubleEndedIterator for Graphemes<'a> { #[inline] fn next_back(&mut self) -> Option<&'a str> { use tables::grapheme as gr; - if self.string.len() == 0 { + if self.string.is_empty() { return None; } diff --git a/src/test/bench/shootout-k-nucleotide-pipes.rs b/src/test/bench/shootout-k-nucleotide-pipes.rs index bcd8fbf88523..b777b25243ba 100644 --- a/src/test/bench/shootout-k-nucleotide-pipes.rs +++ b/src/test/bench/shootout-k-nucleotide-pipes.rs @@ -184,7 +184,7 @@ fn main() { for line in rdr.lines() { let line = line.unwrap().trim().to_string(); - if line.len() == 0 { continue; } + if line.is_empty() { continue; } match (line.as_bytes()[0] as char, proc_mode) { diff --git a/src/test/bench/shootout-nbody.rs b/src/test/bench/shootout-nbody.rs index 669a0e86f1e6..de7fb737958f 100644 --- a/src/test/bench/shootout-nbody.rs +++ b/src/test/bench/shootout-nbody.rs @@ -196,7 +196,7 @@ fn shift_mut_ref<'a, T>(r: &mut &'a mut [T]) -> Option<&'a mut T> { use std::mem; use std::raw::Repr; - if r.len() == 0 { return None } + if r.is_empty() { return None } unsafe { let mut raw = r.repr(); let ret = raw.data as *mut T; diff --git a/src/test/run-pass/dst-struct-sole.rs b/src/test/run-pass/dst-struct-sole.rs index d440fb2a216e..c5da5fc0c1a5 100644 --- a/src/test/run-pass/dst-struct-sole.rs +++ b/src/test/run-pass/dst-struct-sole.rs @@ -79,7 +79,7 @@ pub fn main() { // Zero size vec. let f5: &Fat<[isize]> = &Fat { ptr: [] }; - assert!(f5.ptr.len() == 0); + assert!(f5.ptr.is_empty()); let f5: &Fat<[Bar]> = &Fat { ptr: [] }; - assert!(f5.ptr.len() == 0); + assert!(f5.ptr.is_empty()); } diff --git a/src/test/run-pass/dst-struct.rs b/src/test/run-pass/dst-struct.rs index 8b6db23026b8..92253d815958 100644 --- a/src/test/run-pass/dst-struct.rs +++ b/src/test/run-pass/dst-struct.rs @@ -98,9 +98,9 @@ pub fn main() { // Zero size vec. let f5: &Fat<[isize]> = &Fat { f1: 5, f2: "some str", ptr: [] }; - assert!(f5.ptr.len() == 0); + assert!(f5.ptr.is_empty()); let f5: &Fat<[Bar]> = &Fat { f1: 5, f2: "some str", ptr: [] }; - assert!(f5.ptr.len() == 0); + assert!(f5.ptr.is_empty()); // Deeply nested. let f1 = Fat { f1: 5, f2: "some str", ptr: Fat { f1: 8, f2: "deep str", ptr: [1, 2, 3]} };