Why the compiler tells 'Expression was too complex'

Question

I write this code in Xcode, you can try it on playground.

let constraintSize = CGSize(width: 500.0 - 55.0 - 35.0 - 60.0 - 10.0 - 15.0, height: 9999)

the compiler tell this message

expression was too complex to be solved in reasonable time; consider breaking up the expression into distinct sub-expressions

Any ideas why the compiler tell this silly message, since it is clear that it's just a simple calculation.

score 1 · Answer 1 · answered Oct 02 '15 at 14:49

The compiler doesn't like to have expressions as function parameters.

I guess it's more a source code parsing problem than a calculation problem.

The solution is obvious:

let width = 500.0 - 55.0 - 35.0 - 60.0 - 10.0 - 15.0
let constraintSize = CGSize(width: width, height: 9999)

score 1 · Answer 2 · edited May 23 '17 at 11:51

1

Well, obviously this is a language issue. Compiler should have been able to execute this simple expression. However, in some cases its been observed that long expressions eat up 100% CPU leading to deadlock.

Look at this thread and this thread for more information. Guess you already know the solution in your case so not posting it :).

edited May 23 '17 at 11:51

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answered Oct 02 '15 at 14:53

Abhinav

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Why the compiler tells 'Expression was too complex'

2 Answers2