NSTimeInterval is a double, thus it cannot take a nil, and 0 represents something that should happen immediately. Is there a constant that means "never"... or an astronomically huge value, or should I use -1?
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devios1
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4`double` can take `inf` values. You can test with `isinf(x)` or `(x > DBL_MAX)`. – s.bandara Jan 28 '15 at 19:16
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As suggested by s.bandara, use a very large number to treat a time interval as "infinite" or "never".
DBL_MAX is the largest value a double can hold. This macro is declared in float.h:
#define DBL_MAX (9.999999999999999e999)
JAL
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DBL_MAX is as close to infinity as a double value can get. I've made this answer a community wiki based on the comment on the question. You are free to edit it to improve the answer. – JAL Nov 19 '15 at 04:50
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No, it's not, there's a special value in IEEE 754 floating point to represent infinity. I can't really see how to edit this without rewriting it completely. – jscs Nov 19 '15 at 05:04
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So feel free to write your own answer if you feel that this answer is deficient. – JAL Nov 19 '15 at 12:28
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In Swift, use TimeInterval.infinity. For example, in SwiftUI to conditionally enable a timeline view to update every second or never, use:
TimelineView(.periodic(from: start, by: isRunning ? 1 : .infinity))
Edward Brey
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