if case ... where ...{} 报错
var age = 19if case 10...19 = age where age >= 18
{
print(age)
}抛出异常：Expected ',' joining parts of a multi-clause condition
error: MyPlayground.playground:16:39: error: top-level statement cannot begin with a closure expression
if case 10...19 = age where age >= 18 {
^
如果加上逗号分隔的话：
if case 10...19 = age , where age >= 18 { print(age) }Closure expression is unused
error: MyPlayground.playground:16:41: error: top-level statement cannot begin with a closure expression
if case 10...19 = age , where age >= 18 {
^
