Convert code from Objective-C to Swift

Question

I've got this line of code in Objective-C and I absolutely need to "translate it" to Swift.

BOOL hasBlur = blurRadius > __FLT_EPSILON__

Unfortunately I get this error:

Use of unresolved identifier __FLT_EPSILON_

Can you help me? Thanks

score 6 · Answer 1 · edited Jan 03 '19 at 08:35

6

For swift 3.1 OR above

CGFloat.ulpOfOne

OR

Double.ulpOfOne

edited Jan 03 '19 at 08:35

Martin R

answered Apr 03 '17 at 15:07

Hiren Panchal

Martin R · Accepted Answer · 2019-01-03T08:34:26.533

4

__FLT_EPSILON__ is a predefined macro of the compiler, apparently not available in Swift. But <float.h> defines

#define FLT_EPSILON __FLT_EPSILON__

and this is available in Swift as well:

let hasBlur = blurRadius > FLT_EPSILON

Update: Starting with Swift 4, FLT_EPSILON is deprecated. See Hiren Panchal's answer for an up-to-date solution.

edited Jan 03 '19 at 08:34

answered Aug 25 '14 at 19:21

Martin R

score 0 · Answer 3 · edited May 23 '17 at 12:18

0

Looks like it comes from a line of Objective C that looked like:

#define __FLT_EPSILON__ 1.19209290e-7F

(Source: this thread). So you can safely replace it here with its literal value.

edited May 23 '17 at 12:18

Community

answered Aug 25 '14 at 18:42

Patrick Collins

score 0 · Answer 4 · answered Sep 08 '16 at 02:30

0

just use this: let FLT_EPSILON = CGFloat(FLT_EPSILON)

answered Sep 08 '16 at 02:30

dyljqq

4 Answers4