sp >>>= 0;
						const str = encoder.encode(String(loadValue(sp + 8)));
						storeValue(sp + 16, str);
						setInt64(sp + 24, str.length);
					},

					// valueLoadString(v ref, b []byte)
					"syscall/js.valueLoadString": (sp) => {
						sp >>>= 0;
						const str = loadValue(sp + 8);
						loadSlice(sp + 16).set(str);
					},

					// func valueInstanceOf(v ref, t ref) bool

	b.ReportAllocs()
	str := strings.Repeat("x", 16<<10)
	for i := 0; i < b.N; i++ {
		br := NewReader(strings.NewReader(str))
		n, err := io.Copy(io.Discard, br)
		if err != nil {
			b.Fatal(err)
		}
		if n != int64(len(str)) {
			b.Fatal("wrong length")
		}
	}
}

func BenchmarkWriterEmpty(b *testing.B) {
	b.ReportAllocs()
	str := strings.Repeat("x", 1<<10)

func check(t *testing.T, testname string, buf *Buffer, s string) {
	bytes := buf.Bytes()
	str := buf.String()
	if buf.Len() != len(bytes) {
		t.Errorf("%s: buf.Len() == %d, len(buf.Bytes()) == %d", testname, buf.Len(), len(bytes))
	}

	if buf.Len() != len(str) {
		t.Errorf("%s: buf.Len() == %d, len(buf.String()) == %d", testname, buf.Len(), len(str))
	}

	if buf.Len() != len(s) {

		0, // v2
		0, // v3
		0, // i4
		0, // i5
		0, // u6
		f7,
		f8,
		0, // s9
		0, // s10
		1
	};

	const char __cgodebug_str__9[] = s9;
	const unsigned long long __cgodebug_strlen__9 = sizeof(s9)-1;
	const char __cgodebug_str__10[] = s10;
	const unsigned long long __cgodebug_strlen__10 = sizeof(s10)-1;

and again invokes the system C compiler, to produce an object file

returnAfterGrowFromGo(void)
{
	extern int goReturnVal(void);
	return goReturnVal();
}

void
callGoWithString(void)
{
	extern void goWithString(GoString);
	const char *str = "string passed from C to Go";
	goWithString((GoString){str, strlen(str)});

func (p *Parser) positiveAtoi(str string) int64 {
	value, err := strconv.ParseInt(str, 0, 64)
	if err != nil {
		p.errorf("%s", err)
	}
	if value < 0 {
		p.errorf("%s overflows int64", str)
	}
	return value
}

func (p *Parser) atoi(str string) uint64 {
	value, err := strconv.ParseUint(str, 0, 64)
	if err != nil {
		p.errorf("%s", err)
	}

	for _, call := range f.Calls {
		if call.Done {
			continue
		}
		start := f.offset(call.Call.Pos())
		end := f.offset(call.Call.End())
		str, nu := p.rewriteCall(f, call)
		if str != "" {
			f.Edit.Replace(start, end, str)
			if nu {
				needsUnsafe = true
			}
		}
	}
	return needsUnsafe
}

// rewriteCall rewrites one call to add pointer checks.

Redeclaration does not introduce a new variable; it just assigns a new value to the original.
</p>

<pre>
field1, offset := nextField(str, 0)
field2, offset := nextField(str, offset)  // redeclares offset
a, a := 1, 2                              // illegal: double declaration of a or no new variable if a was declared elsewhere
</pre>

<p>

		case makeReg:
			r := testNonEmptyReader{strings.NewReader(maker.str)}
			fr = &regFileReader{r, maker.size}
		case makeSparse:
			if !validateSparseEntries(maker.spd, maker.size) {
				t.Fatalf("invalid sparse map: %v", maker.spd)
			}
			sph := invertSparseEntries(maker.spd, maker.size)
			r := testNonEmptyReader{strings.NewReader(maker.makeReg.str)}
			fr = &regFileReader{r, maker.makeReg.size}

	args   []string // Formal arguments.
	tokens []Token  // Body of macro.
}

// Tokenize turns a string into a list of Tokens; used to parse the -D flag and in tests.
func Tokenize(str string) []Token {
	t := NewTokenizer("command line", strings.NewReader(str), nil)
	var tokens []Token
	for {
		tok := t.Next()
		if tok == scanner.EOF {
			break
		}
		tokens = append(tokens, Make(tok, t.Text()))
	}
	return tokens