10 examples of 'zero value' in Go

1012
func (t *StructType) ZeroValue() string { return fmt.Sprintf("%s{}", t) }

151
func Zero(value *big.Int) bool {
152
	if value == nil || value.Sign() == 0 {
153
		return true
154
	}
155
	return false
156
}

257
func Zero(data []byte) {
258
	for i := 0; i < len(data); i++ {
259
		data[i] = 0
260
	}
261
}

540
func positiveZeroValue() Value {
541
	return Value{valueNumber, __PositiveZero__}
542
}

89
func ZeroValue(t ValueType) interface{} {
90
	switch t {
91
	case TFloat:
92
		return float64(0)
93
	case TInt:
94
		return int64(0)
95
	case TString:
96
		return ""
97
	case TBool:
98
		return false
99
	case TRegex:
100
		return (*regexp.Regexp)(nil)
101
	case TTime:
102
		return time.Time{}
103
	case TDuration:
104
		return time.Duration(0)
105
	case TLambda:
106
		return (*LambdaNode)(nil)
107
	case TList:
108
		return []interface{}(nil)
109
	case TStar:
110
		return (*StarNode)(nil)
111
	case TMissing:
112
		return (*Missing)(nil)
113
	default:
114
		return errors.New("invalid type")
115
	}
116
}

9
func zero(x uint64) uint64 {
10
	if x == 0 {
11
		return 1
12
	}
13
	return 0
14
	// branchless:
15
	// return ((x>>1 | x&1) - 1) >> 63
16
}

279
func (gen *Generator) ValueZero(t *types.Type) string {
280
	rt := gen.R.Resolve(t, gen.Package)
281
	k := rt.Kind()
282
	switch k {
283
	case types.BlobKind:
284
		return fmt.Sprintf("%sNewEmptyBlob()", gen.TypesPackage)
285
	case types.BoolKind:
286
		return fmt.Sprintf("%sBool(false)", gen.TypesPackage)
287
	case types.NumberKind:
288
		return fmt.Sprintf("%s%s(0)", gen.TypesPackage, kindToString(k))
289
	case types.ListKind, types.MapKind, types.RefKind, types.SetKind:
290
		return gen.UserZero(t)
291
	case types.PackageKind:
292
		return fmt.Sprintf("%sNewPackage()", gen.TypesPackage)
293
	case types.StringKind:
294
		return fmt.Sprintf(`%sNewString("")`, gen.TypesPackage)
295
	case types.StructKind:
296
		return fmt.Sprintf("New%s()", gen.UserName(rt))
297
	case types.ValueKind:
298
		// TODO: Use nil here
299
		return fmt.Sprintf("%sBool(false)", gen.TypesPackage)
300
	case types.TypeKind:
301
		return fmt.Sprintf("%sType{R: ref.Ref{}}", gen.TypesPackage)
302
	}
303
	panic("unreachable")
304
}

46
func zero() *big.Int { return big.NewInt(0) }

59
func (s U8Slice) ZeroMoreThan(i int) bool			{ return false }

82
func (c *Conv) InitZero(cr anyvec.Creator) {
83
	filterSize := c.FilterWidth * c.FilterHeight * c.InputDepth
84
	c.Filters = anydiff.NewVar(cr.MakeVector(filterSize * c.FilterCount))
85
	c.Biases = anydiff.NewVar(cr.MakeVector(c.FilterCount))
86
	c.Conver = CurrentConverMaker()(*c)
87
}