func NewItem(value interface{}, expiration *time.Time) Item {
	var expiration2 time.Time
	if expiration != nil {
		expiration2 = *expiration
	}
	return Item{
		value:      value,
		expiration: expiration2,
		expires:    (expiration != nil),
	}
}
NewItem creates an item with the specified value and optional expiration.
package ttlmap
import (
	"math"
	"time"
)
type Item struct {
	value      interface{}
	expiration time.Time
	expires    bool
}