use append

R=gri, r, r2
CC=golang-dev
https://golang.org/cl/2743042

src/cmd/cgo/ast.go

@@ -136,14 +136,6 @@ func (f *File) saveRef(x interface{}, context string) {
 		// so that we will be able to distinguish a "top-level C"
 		// from a local C.
 		if l, ok := sel.X.(*ast.Ident); ok && l.Name == "C" {
-			i := len(f.Ref)
-			if i >= cap(f.Ref) {
-				new := make([]*Ref, 2*i)
-				for j, v := range f.Ref {
-					new[j] = v
-				}
-				f.Ref = new
-			}
 			if context == "as2" {
 				context = "expr"
 			}
@@ -155,12 +147,11 @@ func (f *File) saveRef(x interface{}, context string) {
 				}
 				f.Name[goname] = name
 			}
-			f.Ref = f.Ref[0 : i+1]
-			f.Ref[i] = &Ref{
+			f.Ref = append(f.Ref, &Ref{
 				Name:    name,
 				Expr:    n,
 				Context: context,
-			}
+			})
 			return
 		}
 	}
@@ -186,20 +177,10 @@ func (f *File) saveExport(x interface{}, context string) {
 			error(c.Position, "export missing name")
 		}
 
-		if f.ExpFunc == nil {
-			f.ExpFunc = make([]*ExpFunc, 0, 8)
-		}
-		i := len(f.ExpFunc)
-		if i >= cap(f.ExpFunc) {
-			new := make([]*ExpFunc, i, 2*i)
-			copy(new, f.ExpFunc)
-			f.ExpFunc = new
-		}
-		f.ExpFunc = f.ExpFunc[0 : i+1]
-		f.ExpFunc[i] = &ExpFunc{
+		f.ExpFunc = append(f.ExpFunc, &ExpFunc{
 			Func:    n,
 			ExpName: name,
-		}
+		})
 		break
 	}
 }

src/cmd/cgo/gcc.go

@@ -495,7 +495,7 @@ func (p *Package) gccCmd() []string {
 // returns the corresponding DWARF data and any messages
 // printed to standard error.
 func (p *Package) gccDebug(stdin []byte) *dwarf.Data {
-	runGcc(stdin, concat(p.gccCmd(), p.GccOptions))
+	runGcc(stdin, append(p.gccCmd(), p.GccOptions...))
 
 	// Try to parse f as ELF and Mach-O and hope one works.
 	var f interface {
@@ -521,7 +521,7 @@ func (p *Package) gccDebug(stdin []byte) *dwarf.Data {
 // and its included files.
 func (p *Package) gccDefines(stdin []byte) string {
 	base := []string{p.gccName(), p.gccMachine(), "-E", "-dM", "-xc", "-"}
-	stdout, _ := runGcc(stdin, concat(base, p.GccOptions))
+	stdout, _ := runGcc(stdin, append(base, p.GccOptions...))
 	return stdout
 }
 
@@ -530,7 +530,7 @@ func (p *Package) gccDefines(stdin []byte) string {
 // gcc to fail.
 func (p *Package) gccErrors(stdin []byte) string {
 	// TODO(rsc): require failure
-	args := concat(p.gccCmd(), p.GccOptions)
+	args := append(p.gccCmd(), p.GccOptions...)
 	if *debugGcc {
 		fmt.Fprintf(os.Stderr, "$ %s <<EOF\n", strings.Join(args, " "))
 		os.Stderr.Write(stdin)

src/cmd/cgo/util.go

@@ -110,10 +110,3 @@ func slashToUnderscore(c int) int {
 	}
 	return c
 }
-
-func concat(a, b []string) []string {
-	c := make([]string, len(a)+len(b))
-	copy(c, a)
-	copy(c[len(a):], b)
-	return c
-}

src/cmd/hgpatch/main.go

@@ -318,11 +318,9 @@ func hgRename(dst, src string) os.Error {
 	return err
 }
 
-func copy(a []string) []string {
+func dup(a []string) []string {
 	b := make([]string, len(a))
-	for i, s := range a {
-		b[i] = s
-	}
+	copy(b, a)
 	return b
 }
 
@@ -379,7 +377,7 @@ func run(argv []string, input []byte) (out string, err os.Error) {
 	return
 
 Error:
-	err = &runError{copy(argv), err}
+	err = &runError{dup(argv), err}
 	return
 }
 

src/cmd/prof/gopprof

@@ -2736,6 +2736,7 @@ sub IsSymbolizedProfileFile {
 
 sub CheckSymbolPage {
   my $url = SymbolPageURL();
+print STDERR "Read $url\n";
   open(SYMBOL, "$CURL -s '$url' |");
   my $line = <SYMBOL>;
   $line =~ s/\r//g;         # turn windows-looking lines into unix-looking lines
@@ -2816,7 +2817,7 @@ sub ResolveRedirectionForCurl {
 # $main::prog to have the correct program name.
 sub ReadSymbols {
   my $in = shift;
-  my $map = {};
+  my $map = shift;
   while (<$in>) {
     s/\r//g;         # turn windows-looking lines into unix-looking lines
     # Removes all the leading zeroes from the symbols, see comment below.
@@ -2858,20 +2859,30 @@ sub FetchSymbols {
   my @pcs = grep { !$seen{$_}++ } keys(%$pcset);  # uniq
 
   if (!defined($symbol_map)) {
-    my $post_data = join("+", sort((map {"0x" . "$_"} @pcs)));
-
-    open(POSTFILE, ">$main::tmpfile_sym");
-    print POSTFILE $post_data;
-    close(POSTFILE);
-
-    my $url = SymbolPageURL();
-    $url = ResolveRedirectionForCurl($url);
-    my $command_line = "$CURL -sd '\@$main::tmpfile_sym' '$url'";
-    # We use c++filt in case $SYMBOL_PAGE gives us mangled symbols.
-    my $cppfilt = $obj_tool_map{"c++filt"};
-    open(SYMBOL, "$command_line | $cppfilt |") or error($command_line);
-    $symbol_map = ReadSymbols(*SYMBOL{IO});
-    close(SYMBOL);
+    $symbol_map = {};
+    my @toask = @pcs;
+    while (@toask > 0) {
+      my $n = @toask;
+      if ($n > 49) { $n = 49; }
+      my @thisround = @toask[0..$n];
+my $t = @toask;
+print STDERR "$n $t\n";
+      @toask = @toask[($n+1)..(@toask-1)];
+      my $post_data = join("+", sort((map {"0x" . "$_"} @thisround)));
+      open(POSTFILE, ">$main::tmpfile_sym");
+      print POSTFILE $post_data;
+      close(POSTFILE);
+
+print STDERR "SYMBL!\n";
+      my $url = SymbolPageURL();
+      $url = ResolveRedirectionForCurl($url);
+      my $command_line = "$CURL -sd '\@$main::tmpfile_sym' '$url'";
+      # We use c++filt in case $SYMBOL_PAGE gives us mangled symbols.
+      my $cppfilt = $obj_tool_map{"c++filt"};
+      open(SYMBOL, "$command_line | $cppfilt |") or error($command_line);
+      ReadSymbols(*SYMBOL{IO}, $symbol_map);
+      close(SYMBOL);
+    }
   }
 
   my $symbols = {};

src/pkg/bufio/bufio.go

@@ -293,7 +293,6 @@ func (b *Reader) ReadBytes(delim byte) (line []byte, err os.Error) {
 	// accumulating full buffers.
 	var frag []byte
 	var full [][]byte
-	nfull := 0
 	err = nil
 
 	for {
@@ -310,24 +309,12 @@ func (b *Reader) ReadBytes(delim byte) (line []byte, err os.Error) {
 		// Make a copy of the buffer.
 		buf := make([]byte, len(frag))
 		copy(buf, frag)
-
-		// Grow list if needed.
-		if full == nil {
-			full = make([][]byte, 16)
-		} else if nfull >= len(full) {
-			newfull := make([][]byte, len(full)*2)
-			copy(newfull, full)
-			full = newfull
-		}
-
-		// Save buffer
-		full[nfull] = buf
-		nfull++
+		full = append(full, buf)
 	}
 
 	// Allocate new buffer to hold the full pieces and the fragment.
 	n := 0
-	for i := 0; i < nfull; i++ {
+	for i := range full {
 		n += len(full[i])
 	}
 	n += len(frag)
@@ -335,9 +322,8 @@ func (b *Reader) ReadBytes(delim byte) (line []byte, err os.Error) {
 	// Copy full pieces and fragment in.
 	buf := make([]byte, n)
 	n = 0
-	for i := 0; i < nfull; i++ {
-		copy(buf[n:], full[i])
-		n += len(full[i])
+	for i := range full {
+		n += copy(buf[n:], full[i])
 	}
 	copy(buf[n:], frag)
 	return buf, err

src/pkg/bytes/bytes.go

@@ -545,7 +545,7 @@ func resize(n int) int {
 // Add appends the contents of t to the end of s and returns the result.
 // If s has enough capacity, it is extended in place; otherwise a
 // new array is allocated and returned.
-func Add(s, t []byte) []byte {
+func Add(s, t []byte) []byte { // TODO
 	lens := len(s)
 	lent := len(t)
 	if lens+lent <= cap(s) {
@@ -562,7 +562,7 @@ func Add(s, t []byte) []byte {
 // AddByte appends byte t to the end of s and returns the result.
 // If s has enough capacity, it is extended in place; otherwise a
 // new array is allocated and returned.
-func AddByte(s []byte, t byte) []byte {
+func AddByte(s []byte, t byte) []byte { // TODO
 	lens := len(s)
 	if lens+1 <= cap(s) {
 		s = s[0 : lens+1]

src/pkg/crypto/tls/handshake_messages.go

@@ -315,19 +315,6 @@ func (m *serverHelloMsg) marshal() []byte {
 	return x
 }
 
-func append(slice []string, elem string) []string {
-	if len(slice) < cap(slice) {
-		slice = slice[0 : len(slice)+1]
-		slice[len(slice)-1] = elem
-		return slice
-	}
-
-	fresh := make([]string, len(slice)+1, cap(slice)*2+1)
-	copy(fresh, slice)
-	fresh[len(slice)] = elem
-	return fresh
-}
-
 func (m *serverHelloMsg) unmarshal(data []byte) bool {
 	if len(data) < 42 {
 		return false

src/pkg/crypto/x509/x509.go

@@ -187,19 +187,19 @@ func (n *Name) fillFromRDNSequence(rdns *rdnSequence) {
 			case 5:
 				n.SerialNumber = value
 			case 6:
-				n.Country = appendString(n.Country, value)
+				n.Country = append(n.Country, value)
 			case 7:
-				n.Locality = appendString(n.Locality, value)
+				n.Locality = append(n.Locality, value)
 			case 8:
-				n.Province = appendString(n.Province, value)
+				n.Province = append(n.Province, value)
 			case 9:
-				n.StreetAddress = appendString(n.StreetAddress, value)
+				n.StreetAddress = append(n.StreetAddress, value)
 			case 10:
-				n.Organization = appendString(n.Organization, value)
+				n.Organization = append(n.Organization, value)
 			case 11:
-				n.OrganizationalUnit = appendString(n.OrganizationalUnit, value)
+				n.OrganizationalUnit = append(n.OrganizationalUnit, value)
 			case 17:
-				n.PostalCode = appendString(n.PostalCode, value)
+				n.PostalCode = append(n.PostalCode, value)
 			}
 		}
 	}
@@ -501,17 +501,6 @@ func parsePublicKey(algo PublicKeyAlgorithm, asn1Data []byte) (interface{}, os.E
 	panic("unreachable")
 }
 
-func appendString(in []string, v string) (out []string) {
-	if cap(in)-len(in) < 1 {
-		out = make([]string, len(in)+1, len(in)*2+1)
-		copy(out, in)
-	} else {
-		out = in[0 : len(in)+1]
-	}
-	out[len(in)] = v
-	return out
-}
-
 func parseCertificate(in *certificate) (*Certificate, os.Error) {
 	out := new(Certificate)
 	out.Raw = in.TBSCertificate.Raw
@@ -601,10 +590,10 @@ func parseCertificate(in *certificate) (*Certificate, os.Error) {
 					}
 					switch v.Tag {
 					case 1:
-						out.EmailAddresses = appendString(out.EmailAddresses, string(v.Bytes))
+						out.EmailAddresses = append(out.EmailAddresses, string(v.Bytes))
 						parsedName = true
 					case 2:
-						out.DNSNames = appendString(out.DNSNames, string(v.Bytes))
+						out.DNSNames = append(out.DNSNames, string(v.Bytes))
 						parsedName = true
 					}
 				}

src/pkg/debug/dwarf/type.go

@@ -451,14 +451,7 @@ func (d *Data) Type(off Offset) (Type, os.Error) {
 				f.ByteSize, _ = kid.Val(AttrByteSize).(int64)
 				f.BitOffset, _ = kid.Val(AttrBitOffset).(int64)
 				f.BitSize, _ = kid.Val(AttrBitSize).(int64)
-				n := len(t.Field)
-				if n >= cap(t.Field) {
-					fld := make([]*StructField, n, n*2)
-					copy(fld, t.Field)
-					t.Field = fld
-				}
-				t.Field = t.Field[0 : n+1]
-				t.Field[n] = f
+				t.Field = append(t.Field, f)
 			}
 		}
 
@@ -554,14 +547,7 @@ func (d *Data) Type(off Offset) (Type, os.Error) {
 			case TagUnspecifiedParameters:
 				tkid = &DotDotDotType{}
 			}
-			n := len(t.ParamType)
-			if n >= cap(t.ParamType) {
-				param := make([]Type, n, n*2)
-				copy(param, t.ParamType)
-				t.ParamType = param
-			}
-			t.ParamType = t.ParamType[0 : n+1]
-			t.ParamType[n] = tkid
+			t.ParamType = append(t.ParamType, tkid)
 		}
 
 	case TagTypedef:

src/pkg/debug/macho/file.go

@@ -302,15 +302,7 @@ func NewFile(r io.ReaderAt) (*File, os.Error) {
 }
 
 func (f *File) pushSection(sh *Section, r io.ReaderAt) {
-	n := len(f.Sections)
-	if n >= cap(f.Sections) {
-		m := (n + 1) * 2
-		new := make([]*Section, n, m)
-		copy(new, f.Sections)
-		f.Sections = new
-	}
-	f.Sections = f.Sections[0 : n+1]
-	f.Sections[n] = sh
+	f.Sections = append(f.Sections, sh)
 	sh.sr = io.NewSectionReader(r, int64(sh.Offset), int64(sh.Size))
 	sh.ReaderAt = sh.sr
 }

src/pkg/exp/eval/func.go

@@ -43,14 +43,7 @@ type codeBuf struct {
 func newCodeBuf() *codeBuf { return &codeBuf{make(code, 0, 16)} }
 
 func (b *codeBuf) push(instr func(*Thread)) {
-	n := len(b.instrs)
-	if n >= cap(b.instrs) {
-		a := make(code, n, n*2)
-		copy(a, b.instrs)
-		b.instrs = a
-	}
-	b.instrs = b.instrs[0 : n+1]
-	b.instrs[n] = instr
+	b.instrs = append(b.instrs, instr)
 }
 
 func (b *codeBuf) nextPC() uint { return uint(len(b.instrs)) }

src/pkg/exp/nacl/srpc/server.go

@@ -53,14 +53,7 @@ var rpcMethod []method
 //	s	string
 //
 func Add(name, fmt string, handler Handler) {
-	n := len(rpcMethod)
-	if n >= cap(rpcMethod) {
-		a := make([]method, n, (n+4)*2)
-		copy(a, rpcMethod)
-		rpcMethod = a
-	}
-	rpcMethod = rpcMethod[0 : n+1]
-	rpcMethod[n] = method{name, fmt, handler}
+	rpcMethod = append(rpcMethod, method{name, fmt, handler})
 }
 
 // Serve accepts new SRPC connections from the file descriptor fd

src/pkg/exp/ogle/process.go

@@ -390,15 +390,7 @@ func (p *Process) causesToEvents() ([]Event, os.Error) {
 // postEvent appends an event to the posted queue.  These events will
 // be processed before any currently pending events.
 func (p *Process) postEvent(ev Event) {
-	n := len(p.posted)
-	m := n * 2
-	if m == 0 {
-		m = 4
-	}
-	posted := make([]Event, n+1, m)
-	copy(posted, p.posted)
-	posted[n] = ev
-	p.posted = posted
+	p.posted = append(p.posted, ev)
 }
 
 // processEvents processes events in the event queue until no events

src/pkg/flag/flag_test.go

@@ -161,10 +161,7 @@ func (f *flagVar) String() string {
 }
 
 func (f *flagVar) Set(value string) bool {
-	n := make(flagVar, len(*f)+1)
-	copy(n, *f)
-	*f = n
-	(*f)[len(*f)-1] = value
+	*f = append(*f, value)
 	return true
 }
 

src/pkg/go/ast/scope.go

@@ -66,17 +66,9 @@ func (s *Scope) Insert(obj *Object) *Object {
 
 
 func (s *Scope) append(obj *Object) {
-	n := len(s.Objects)
-	if n >= cap(s.Objects) {
-		new := make([]*Object, 2*n)
-		copy(new, s.Objects)
-		s.Objects = new
-	}
-	s.Objects = s.Objects[0 : n+1]
-	s.Objects[n] = obj
+	s.Objects = append(s.Objects, obj)
 }
 
-
 // ----------------------------------------------------------------------------
 // Objects
 

src/pkg/go/doc/comment.go

@@ -62,16 +62,7 @@ func CommentText(comment *ast.CommentGroup) string {
 
 		// Walk lines, stripping trailing white space and adding to list.
 		for _, l := range cl {
-			l = stripTrailingWhitespace(l)
-			// Add to list.
-			n := len(lines)
-			if n+1 >= cap(lines) {
-				newlines := make([]string, n, 2*cap(lines))
-				copy(newlines, lines)
-				lines = newlines
-			}
-			lines = lines[0 : n+1]
-			lines[n] = l
+			lines = append(lines, stripTrailingWhitespace(l))
 		}
 	}
 

src/pkg/go/doc/doc.go

@@ -277,12 +277,9 @@ func (doc *docReader) addDecl(decl ast.Decl) {
 
 
 func copyCommentList(list []*ast.Comment) []*ast.Comment {
-	nlist := make([]*ast.Comment, len(list))
-	copy(nlist, list)
-	return nlist
+	return append([]*ast.Comment(nil), list...)
 }
 
-
 var (
 	bug_markers = regexp.MustCompile("^/[/*][ \t]*BUG\\(.*\\):[ \t]*") // BUG(uid):
 	bug_content = regexp.MustCompile("[^ \n\r\t]+")                    // at least one non-whitespace char

src/pkg/html/token.go

@@ -374,26 +374,15 @@ func (z *Tokenizer) Token() Token {
 	case Text:
 		t.Data = string(z.Text())
 	case StartTag, EndTag, SelfClosingTag:
-		var (
-			attr []Attribute
-			a    int
-		)
+		var attr []Attribute
 		name, remaining := z.TagName()
 		for remaining {
 			var key, val []byte
 			key, val, remaining = z.TagAttr()
-			if a == len(attr) {
-				// Grow the attr slice.
-				n := 4 + 2*a
-				attr1 := make([]Attribute, n, n)
-				copy(attr1, attr)
-				attr = attr1
-			}
-			attr[a] = Attribute{string(key), string(val)}
-			a++
+			attr = append(attr, Attribute{string(key), string(val)})
 		}
 		t.Data = string(name)
-		t.Attr = attr[0:a]
+		t.Attr = attr
 	}
 	return t
 }

src/pkg/image/format.go

@@ -29,15 +29,7 @@ var formats []format
 // Decode is the function that decodes the encoded image.
 // DecodeConfig is the function that decodes just its configuration.
 func RegisterFormat(name, magic string, decode func(io.Reader) (Image, os.Error), decodeConfig func(io.Reader) (Config, os.Error)) {
-	n := len(formats)
-	if n == cap(formats) {
-		x := make([]format, n+1, 2*n+4)
-		copy(x, formats)
-		formats = x
-	} else {
-		formats = formats[0 : n+1]
-	}
-	formats[n] = format{name, magic, decode, decodeConfig}
+	formats = append(formats, format{name, magic, decode, decodeConfig})
 }
 
 // A reader is an io.Reader that can also peek ahead.

src/pkg/json/scanner.go

@@ -155,18 +155,7 @@ func (s *scanner) eof() int {
 
 // pushParseState pushes a new parse state p onto the parse stack.
 func (s *scanner) pushParseState(p int) {
-	n := len(s.parseState)
-	if n >= cap(s.parseState) {
-		if n == 0 {
-			s.parseState = make([]int, 0, 16)
-		} else {
-			ps := make([]int, n, 2*n)
-			copy(ps, s.parseState)
-			s.parseState = ps
-		}
-	}
-	s.parseState = s.parseState[0 : n+1]
-	s.parseState[n] = p
+	s.parseState = append(s.parseState, p)
 }
 
 // popParseState pops a parse state (already obtained) off the stack

src/pkg/net/hosts.go

@@ -44,7 +44,7 @@ func readHosts() {
 			}
 			for i := 1; i < len(f); i++ {
 				h := f[i]
-				hs[h] = appendHost(hs[h], f[0])
+				hs[h] = append(hs[h], f[0])
 			}
 		}
 		// Update the data cache.
@@ -55,18 +55,6 @@ func readHosts() {
 	}
 }
 
-func appendHost(hosts []string, address string) []string {
-	n := len(hosts)
-	if n+1 > cap(hosts) { // reallocate
-		a := make([]string, n, 2*n+1)
-		copy(a, hosts)
-		hosts = a
-	}
-	hosts = hosts[0 : n+1]
-	hosts[n] = address
-	return hosts
-}
-
 // lookupStaticHosts looks up the addresses for the given host from /etc/hosts.
 func lookupStaticHost(host string) []string {
 	hosts.Lock()

src/pkg/os/dir_darwin.go

@@ -64,13 +64,7 @@ func (file *File) Readdirnames(count int) (names []string, err Error) {
 				continue
 			}
 			count--
-			if len(names) == cap(names) {
-				nnames := make([]string, len(names), 2*len(names))
-				copy(nnames, names)
-				names = nnames
-			}
-			names = names[0 : len(names)+1]
-			names[len(names)-1] = name
+			names = append(names, name)
 		}
 	}
 	return names, nil

src/pkg/os/dir_freebsd.go

@@ -59,13 +59,7 @@ func (file *File) Readdirnames(count int) (names []string, err Error) {
 				continue
 			}
 			count--
-			if len(names) == cap(names) {
-				nnames := make([]string, len(names), 2*len(names))
-				copy(nnames, names)
-				names = nnames
-			}
-			names = names[0 : len(names)+1]
-			names[len(names)-1] = name
+			names = append(names, name)
 		}
 	}
 	return names, nil

src/pkg/os/dir_linux.go

@@ -62,13 +62,7 @@ func (file *File) Readdirnames(count int) (names []string, err Error) {
 				continue
 			}
 			count--
-			if len(names) == cap(names) {
-				nnames := make([]string, len(names), 2*len(names))
-				copy(nnames, names)
-				names = nnames
-			}
-			names = names[0 : len(names)+1]
-			names[len(names)-1] = name
+			names = append(names, name)
 		}
 	}
 	return names, nil

src/pkg/os/dir_nacl.go

@@ -62,13 +62,7 @@ func (file *File) Readdirnames(count int) (names []string, err Error) {
 				continue
 			}
 			count--
-			if len(names) == cap(names) {
-				nnames := make([]string, len(names), 2*len(names))
-				copy(nnames, names)
-				names = nnames
-			}
-			names = names[0 : len(names)+1]
-			names[len(names)-1] = name
+			names = append(names, name)
 		}
 	}
 	return names, nil

src/pkg/os/env_windows.go

@@ -87,13 +87,7 @@ func Environ() []string {
 			if i <= from {
 				break
 			}
-			if len(r) == cap(r) {
-				nr := make([]string, len(r), 2*len(r))
-				copy(nr, r)
-				r = nr
-			}
-			r = r[0 : len(r)+1]
-			r[len(r)-1] = string(utf16.Decode(p[from:i]))
+			r = append(r, string(utf16.Decode(p[from:i])))
 			from = i + 1
 		}
 	}

src/pkg/os/file_windows.go

@@ -157,13 +157,7 @@ func (file *File) Readdir(count int) (fi []FileInfo, err Error) {
 			continue
 		}
 		count--
-		if len(fi) == cap(fi) {
-			nfi := make([]FileInfo, len(fi), 2*len(fi))
-			copy(nfi, fi)
-			fi = nfi
-		}
-		fi = fi[0 : len(fi)+1]
-		fi[len(fi)-1] = f
+		fi = append(fi, f)
 	}
 	return fi, nil
 }

src/pkg/regexp/regexp.go

@@ -816,15 +816,7 @@ func (a *matchArena) addState(s []state, inst instr, prefixed bool, match *match
 			return s
 		}
 	}
-	if l == cap(s) {
-		s1 := make([]state, 2*l)[0:l]
-		copy(s1, s)
-		s = s1
-	}
-	s = s[0 : l+1]
-	s[l].inst = inst
-	s[l].prefixed = prefixed
-	s[l].match = match
+	s = append(s, state{inst, prefixed, match})
 	match.ref++
 	if inst.kind() == _ALT {
 		s = a.addState(s, inst.(*_Alt).left, prefixed, a.copy(match), pos, end)
@@ -1262,21 +1254,14 @@ func (re *Regexp) FindAll(b []byte, n int) [][]byte {
 	if n < 0 {
 		n = len(b) + 1
 	}
-	result := make([][]byte, startSize)
-	i := 0
+	result := make([][]byte, 0, startSize)
 	re.allMatches("", b, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][]byte, 2*i)
-			copy(new, result)
-			result = new
-		}
-		result[i] = b[match[0]:match[1]]
-		i++
+		result = append(result, b[match[0]:match[1]])
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllIndex is the 'All' version of FindIndex; it returns a slice of all
@@ -1287,21 +1272,14 @@ func (re *Regexp) FindAllIndex(b []byte, n int) [][]int {
 	if n < 0 {
 		n = len(b) + 1
 	}
-	result := make([][]int, startSize)
-	i := 0
+	result := make([][]int, 0, startSize)
 	re.allMatches("", b, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][]int, 2*i)
-			copy(new, result)
-			result = new
-		}
-		result[i] = match[0:2]
-		i++
+		result = append(result, match[0:2])
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllString is the 'All' version of FindString; it returns a slice of all
@@ -1312,21 +1290,14 @@ func (re *Regexp) FindAllString(s string, n int) []string {
 	if n < 0 {
 		n = len(s) + 1
 	}
-	result := make([]string, startSize)
-	i := 0
+	result := make([]string, 0, startSize)
 	re.allMatches(s, nil, n, func(match []int) {
-		if i == cap(result) {
-			new := make([]string, 2*i)
-			copy(new, result)
-			result = new
-		}
-		result[i] = s[match[0]:match[1]]
-		i++
+		result = append(result, s[match[0]:match[1]])
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllStringIndex is the 'All' version of FindStringIndex; it returns a
@@ -1337,21 +1308,14 @@ func (re *Regexp) FindAllStringIndex(s string, n int) [][]int {
 	if n < 0 {
 		n = len(s) + 1
 	}
-	result := make([][]int, startSize)
-	i := 0
+	result := make([][]int, 0, startSize)
 	re.allMatches(s, nil, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][]int, 2*i)
-			copy(new, result)
-			result = new
-		}
-		result[i] = match[0:2]
-		i++
+		result = append(result, match[0:2])
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllSubmatch is the 'All' version of FindSubmatch; it returns a slice
@@ -1362,27 +1326,20 @@ func (re *Regexp) FindAllSubmatch(b []byte, n int) [][][]byte {
 	if n < 0 {
 		n = len(b) + 1
 	}
-	result := make([][][]byte, startSize)
-	i := 0
+	result := make([][][]byte, 0, startSize)
 	re.allMatches("", b, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][][]byte, 2*i)
-			copy(new, result)
-			result = new
-		}
 		slice := make([][]byte, len(match)/2)
 		for j := range slice {
 			if match[2*j] >= 0 {
 				slice[j] = b[match[2*j]:match[2*j+1]]
 			}
 		}
-		result[i] = slice
-		i++
+		result = append(result, slice)
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllSubmatchIndex is the 'All' version of FindSubmatchIndex; it returns
@@ -1393,21 +1350,14 @@ func (re *Regexp) FindAllSubmatchIndex(b []byte, n int) [][]int {
 	if n < 0 {
 		n = len(b) + 1
 	}
-	result := make([][]int, startSize)
-	i := 0
+	result := make([][]int, 0, startSize)
 	re.allMatches("", b, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][]int, 2*i)
-			copy(new, result)
-			result = new
-		}
-		result[i] = match
-		i++
+		result = append(result, match)
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllStringSubmatch is the 'All' version of FindStringSubmatch; it
@@ -1418,27 +1368,20 @@ func (re *Regexp) FindAllStringSubmatch(s string, n int) [][]string {
 	if n < 0 {
 		n = len(s) + 1
 	}
-	result := make([][]string, startSize)
-	i := 0
+	result := make([][]string, 0, startSize)
 	re.allMatches(s, nil, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][]string, 2*i)
-			copy(new, result)
-			result = new
-		}
 		slice := make([]string, len(match)/2)
 		for j := range slice {
 			if match[2*j] >= 0 {
 				slice[j] = s[match[2*j]:match[2*j+1]]
 			}
 		}
-		result[i] = slice
-		i++
+		result = append(result, slice)
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }
 
 // FindAllStringSubmatchIndex is the 'All' version of
@@ -1450,19 +1393,12 @@ func (re *Regexp) FindAllStringSubmatchIndex(s string, n int) [][]int {
 	if n < 0 {
 		n = len(s) + 1
 	}
-	result := make([][]int, startSize)
-	i := 0
+	result := make([][]int, 0, startSize)
 	re.allMatches(s, nil, n, func(match []int) {
-		if i == cap(result) {
-			new := make([][]int, 2*i)
-			copy(new, result)
-			result = new
-		}
-		result[i] = match
-		i++
+		result = append(result, match)
 	})
-	if i == 0 {
+	if len(result) == 0 {
 		return nil
 	}
-	return result[0:i]
+	return result
 }

src/pkg/template/template.go

@@ -318,13 +318,7 @@ func words(buf []byte) []string {
 		if start == p { // no text left
 			break
 		}
-		if i == cap(s) {
-			ns := make([]string, 2*cap(s))
-			copy(ns, s)
-			s = ns
-		}
-		s = s[0 : i+1]
-		s[i] = string(buf[start:p])
+		s = append(s, string(buf[start:p]))
 	}
 	return s
 }

src/pkg/testing/regexp.go

@@ -167,17 +167,7 @@ func (cclass *_CharClass) print() {
 
 func (cclass *_CharClass) addRange(a, b int) {
 	// range is a through b inclusive
-	n := len(cclass.ranges)
-	if n >= cap(cclass.ranges) {
-		nr := make([]int, n, 2*n)
-		copy(nr, cclass.ranges)
-		cclass.ranges = nr
-	}
-	cclass.ranges = cclass.ranges[0 : n+2]
-	cclass.ranges[n] = a
-	n++
-	cclass.ranges[n] = b
-	n++
+	cclass.ranges = append(cclass.ranges, a, b)
 }
 
 func (cclass *_CharClass) matches(c int) bool {
@@ -249,15 +239,8 @@ func (nop *_Nop) kind() int { return _NOP }
 func (nop *_Nop) print()    { print("nop") }
 
 func (re *Regexp) add(i instr) instr {
-	n := len(re.inst)
 	i.setIndex(len(re.inst))
-	if n >= cap(re.inst) {
-		ni := make([]instr, n, 2*n)
-		copy(ni, re.inst)
-		re.inst = ni
-	}
-	re.inst = re.inst[0 : n+1]
-	re.inst[n] = i
+	re.inst = append(re.inst, i)
 	return i
 }
 

src/pkg/unicode/maketables.go

@@ -493,15 +493,7 @@ func parseScript(line string, scripts map[string][]Script) {
 		}
 	}
 	name := matches[3]
-	s, ok := scripts[name]
-	if !ok || len(s) == cap(s) {
-		ns := make([]Script, len(s), len(s)+100)
-		copy(ns, s)
-		s = ns
-	}
-	s = s[0 : len(s)+1]
-	s[len(s)-1] = Script{uint32(lo), uint32(hi), name}
-	scripts[name] = s
+	scripts[name] = append(scripts[name], Script{uint32(lo), uint32(hi), name})
 }
 
 // The script tables have a lot of adjacent elements. Fold them together.