Use an example that has more obvious invalid state

amartini51 · Quinn · amartini51 · commit b94cff79e989 · 2024-12-17T16:53:46.000-08:00
Co-authored-by: Quinn &lt;eskimo1@apple.com&gt;
diff --git a/TSPL.docc/LanguageGuide/Concurrency.md b/TSPL.docc/LanguageGuide/Concurrency.md
@@ -1107,8 +1107,8 @@ the code below converts measured temperatures from Fahrenheit to Celsius:
 ```swift
 extension TemperatureLogger {
     func convertFahrenheitToCelsius() {
-        measurements = measurements.map { measurement in
-            (measurement - 32) * 5 / 9
+        for i in measurements.indices {
+            measurements[i] =  (measurements[i] - 32) * 5 / 9
         }
     }
 }

Original file line number	Diff line number	Diff line change
`@@ -1107,8 +1107,8 @@ the code below converts measured temperatures from Fahrenheit to Celsius:`
`1107`	`1107`	```swift
`1108`	`1108`	`extension TemperatureLogger {`
`1109`	`1109`	`func convertFahrenheitToCelsius() {`
`1110`		`- measurements = measurements.map { measurement in`
`1111`		`- (measurement - 32) * 5 / 9`
	`1110`	`+ for i in measurements.indices {`
	`1111`	`+ measurements[i] = (measurements[i] - 32) * 5 / 9`
`1112`	`1112`	`}`
`1113`	`1113`	`}`
`1114`	`1114`	`}`