Method Eval

runtime/sam/expr/cast.go:203–236

(val super.Value)

}

func (c *casterString) Eval(val super.Value) super.Value {
	val = val.Under()
	id := val.Type().ID()
	switch id {
	case super.IDBytes:
		if !utf8.Valid(val.Bytes()) {
			return c.sctx.WrapError("cannot cast to string: invalid UTF-8", val)
		}
		return super.NewValue(super.TypeString, val.Bytes())
	case super.IDString:
		return super.NewValue(super.TypeString, val.Bytes())
	case super.IDInt8, super.IDInt16, super.IDInt32, super.IDInt64:
		return super.NewString(strconv.FormatInt(val.Int(), 10))
	case super.IDUint8, super.IDUint16, super.IDUint32, super.IDUint64:
		return super.NewString(strconv.FormatUint(val.Uint(), 10))
	case super.IDFloat16, super.IDFloat32:
		return super.NewString(strconv.FormatFloat(val.Float(), 'g', -1, 32))
	case super.IDFloat64:
		return super.NewString(strconv.FormatFloat(val.Float(), 'g', -1, 64))
	case super.IDNull:
		return c.sctx.WrapError("cannot cast to string", val)
	}
	if enum, ok := val.Type().(*super.TypeEnum); ok {
		selector := super.DecodeUint(val.Bytes())
		symbol, err := enum.Symbol(int(selector))
		if err != nil {
			return c.sctx.NewError(err)
		}
		return super.NewString(symbol)
	}
	// Otherwise, we'll use a canonical SUP value for the string rep
	// of an arbitrary value cast to a string.
	return super.NewString(sup.FormatValue(val))
}

type casterBytes struct {
	sctx *super.Context