I am familiar with that article and understand float precision hence titled question
how it handles float precision 0.4 + 0.2 = 0.6 and received answer for that- thank you.
I am not familiar with concept of Constant as neither BASIC or Python has it and latter gives different result 0.1 + 0.2 or 0.2+ 0.4, than GO hence my original question.
Excel deals with it as rounding and still float and that is hiding problem.
The very good summary text from previous article:
“x := 0.1 + 0.2 is precisely 0.3 because 0.1 and 0.2 are numeric constants”
Could be put there with some my above example to expand that tour segment and flag as warning how float32 or float64 behaves at base 2.
https://go.dev/tour/basics/15
Things may be obvious, but they aren’t and errors are even in books.
I learn Python and GO also from green book series in easy steps.
The Python decimal module on p 89 does not have information to put numbers as strings Decimal(‘ ’) I notified publisher and also regarding GO to expand on floating point, while old BASIC books and manuals had it (read ~5000 pages of old manuals and ~1000 p from old book since last year incl original 1964 release and code on old hardware 1986-93).
Decimal(0.1) + Decimal(0.2) will give error unless put as string Decimal(‘0.1’) + Decimal(‘0.2’), but allows to add one as string and one as not and easy to make such error.
GO has stable syntax hence it is very good language and I value simplicity.
Cobol deals best decimal as integers- elegant solution and most safe than converting to strings like many modules do.
With GO I also go to beginning too – hence watched mentioned launch video. Interesting is why they have not put originally simple Cobol solution for decimal out of box to avoid all the third party decimal modules and added syntax.
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