Question

例如，下面的代码打印1，这意味着新行被视为语句分隔符：

import UIKit
import PlaygroundSupport

let container = UIView(frame: CGRect(x: 0, y: 0, width: 600, height: 600))

container.backgroundColor = UIColor.green

PlaygroundPage.current.liveView = container

// at this point, we have a 600 x 600 green square to use as a playground "canvas"

var label: UILabel = {
    let l = UILabel()
    l.backgroundColor = UIColor.yellow
    l.text = "This is a longer Label"
    return l
}()

var button: UIButton = {
    let l = UIButton()
    l.backgroundColor = UIColor.red
    l.setTitle("The Button", for: .normal)
    return l
}()

var divView: UIView = {
    let v = UIView()
    v.backgroundColor = UIColor.lightGray
    return v
}()

var headerView: UIView = {
    let v = UIView()
    v.backgroundColor = UIColor.blue
    return v
}()

// add our header view
container.addSubview(headerView)

// add div, label and button as subviews in headerView
headerView.addSubview(divView)
headerView.addSubview(label)
headerView.addSubview(button)

// disable Autoresizing Masks
headerView.translatesAutoresizingMaskIntoConstraints = false
divView.translatesAutoresizingMaskIntoConstraints = false
label.translatesAutoresizingMaskIntoConstraints = false
button.translatesAutoresizingMaskIntoConstraints = false

var vcs: [NSLayoutConstraint]

var views = ["divView": divView, "label": label, "button": button, "headerView": headerView]


// init "header view" - we'll let its contents determine its width and height

// these two formats will simply put the header view at 20,20
vcs = NSLayoutConstraint.constraints(withVisualFormat:
    "H:|-20-[headerView]", options: [], metrics: nil, views: views)
container.addConstraints(vcs)

vcs = NSLayoutConstraint.constraints(withVisualFormat:
    "V:|-20-[headerView]", options: [], metrics: nil, views: views)
container.addConstraints(vcs)


// H: pin label 19 from left
//    pin button 22 from right
//    use 60 spacing between label and button
//    width of label and button auto-determined by text
//    also use .alignAllCenterY to vertically align them
vcs = NSLayoutConstraint.constraints(withVisualFormat:
    "H:|-19-[label]-60-[button]-22-|", options: .alignAllCenterY, metrics: nil, views: views)
headerView.addConstraints(vcs)

// V: pin divView to the top, with a height of 10
vcs = NSLayoutConstraint.constraints(withVisualFormat:
    "V:|[divView(10)]", options: [], metrics: nil, views: views)
headerView.addConstraints(vcs)

// V: pin label to bottom of divView (plus spacing of 20)
//    using .alignAllLeft will pin the divView's left to the label's left
vcs = NSLayoutConstraint.constraints(withVisualFormat:
    "V:[divView]-20-[label]", options: .alignAllLeft, metrics: nil, views: views)
headerView.addConstraints(vcs)

// V: pin button to bottom of divView (plus spacing of 20)
//    using .alignAllRight will pin the divView's right to the button's right
vcs = NSLayoutConstraint.constraints(withVisualFormat:
    "V:[divView]-20-[button]|", options: .alignAllRight, metrics: nil, views: views)
headerView.addConstraints(vcs)

但是，此示例打印3，这意味着将忽略新行：

function f1() {
    return 1
    2
}

console.log(f1());

Javascript如何决定何时忽略换行符，以及何时将其用作语句分隔符？

Javascript如何决定新行字符何时分隔语句？

0 个答案: