Swift: '==' is not a prefix unary operator

Question

I'm building a simple swift 3 application as I am learning it now, and I got this error '==' is not a prefix unary operator

This is my code

@IBAction func convertClicked(_ sender: Any) {
    if let result = tempEntry.text {
        if(result =="") {
            return
        } else {
            if let num = Double(result) {
                let output = num * (9/5) + 32
                ResultLabel.text = String(output)
            }
        }
    }
}

This is how Swift tries to fix it, the comma should not be in the original code — loliki, Jan 09 '17 at 14:43
`if(result =="")` is supposed to be `if(result == "")`... spot the space after the `==` operator. — holex, Jan 09 '17 at 14:46

score 4 · Accepted Answer · answered Jan 09 '17 at 14:46

4

Try to add space after '=='.

Instead of :

if(result =="") {

try:

if(result == "") {

answered Jan 09 '17 at 14:46

Miknash

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Can't wait to hear why -1 :) – Miknash Jan 09 '17 at 14:49
expand answer explaining why space is needed as [answered here](http://stackoverflow.com/a/31302667/6920962), for example. – user28434'mstep Jan 09 '17 at 15:08
1

That's why: http://meta.stackoverflow.com/a/276637/4687348 – FelixSFD Jan 09 '17 at 15:08
user28434 does lack of in depth information makes my answer incorrect? wrong? misleading? @FelixSFD care to explain some more? This one is regarding off topic questions... – Miknash Jan 09 '17 at 15:22
1

Space after = worked in my case – Ananta Prasad Apr 17 '19 at 09:21

Swift: '==' is not a prefix unary operator

1 Answers1