Posted by Trygve on Jun 15, 2020; 6:06am
URL: https://forum.world.st/DateTime-now-nanos-tp5118503p5118507.html

Isn't time represented as numbers like floats; it is meaningless to test for equality. It's only meaningful to test for equality within a tolerance. This gives the, possibly unexpected, π != π (pi != pi).
The reason is that the first pi could be 3.14 while the second could be 3.14159265358979 ---- and the second is, of course, far from accurate.

Hi all.
In Playground I write these lines:

Transcript cr; show: DateAndTime now printString.
Transcript cr; show: (DateAndTime fromSeconds: (DateAndTime now asSeconds))
printString.

and in the Transcript window I get these results:

2020-06-15T14:33:06.630367+10:00
2020-06-15T14:33:06+10:00

I was expecting these two to be the same.

I was hoping to use DateAndTime fromSeconds: and aDateAndTime asSeconds to
convert a DateAndTime to/from a number in order to store it in SQLite, but I
don't like the way the nanos are dropped using this method.
It's all good if I remember to call DateAndTime now truncated, and drop the
nanos myself, but that might be all over the place in my application.

Instead, is there a better way to convert a DateAndTime to and from a
number?  



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