precedencegroup PowerPrecedence {
higherThan: MultiplicationPrecedence
associativity: right
}
infix operator **: PowerPrecedence
func **(base: Double, power: Double) -> Double {
return pow(base, power)
}
higherThan: MultiplicationPrecedence
associativity: right
}
infix operator **: PowerPrecedence
func **(base: Double, power: Double) -> Double {
return pow(base, power)
}
2017-08-18
Swift3 自定義雙目運算符指定結(jié)合規(guī)則和優(yōu)先級的方式改了,都封裝在 precedencegroup 里,視頻中的例子變成這樣了:
infix operator **: MultiplicationPrecedence
func **(base: Double, power: Double) -> Double {
return pow(base, power)
}
其中 MultiplicationPrecedence 表示按乘除法的結(jié)合規(guī)則和優(yōu)先級,對應(yīng)加減法是:AdditionPrecedence
infix operator **: MultiplicationPrecedence
func **(base: Double, power: Double) -> Double {
return pow(base, power)
}
其中 MultiplicationPrecedence 表示按乘除法的結(jié)合規(guī)則和優(yōu)先級,對應(yīng)加減法是:AdditionPrecedence
2017-08-18
發(fā)現(xiàn)swift3.1 extension Int{}中無法調(diào)用stride方法了
error: cannot invoke 'stride' with an argument list of type '(from: Int, to: Int, by: Int)'
error: cannot invoke 'stride' with an argument list of type '(from: Int, to: Int, by: Int)'
2017-07-24