Am 18.02.20 um 12:20 schrieb Nikita Popov: > Hi internals, > > https://github.com/php/php-src/pull/5172 changes var_dump() to use > serialize_precision instead of precision to dump floating-point numbers. > > To recap: serialize_precision defaults to -1, which will print exactly as > many floating-point digits as are needed to represent the number > accurately. precision defaults to 14, which will print a shorter but > potentially inaccurate float representation. > > The motivation here is that var_dump() is debugging functionality and > should print values as accurately as possible. The single most common bug > report we receive is some kind of variation on: > > $sum = 0.1 + 0.2; > var_dump($sum); // float(0.3) > var_dump($sum == 0.3); // bool(false) WTF??? > > After this change, this would instead be: > > $sum = 0.1 + 0.2; > var_dump($sum); // float(0.30000000000000004) > var_dump($sum == 0.3); // bool(false) Makes sense... > > I have little hope that developers will suddenly start understanding > floating-point numbers, but at least this should reduce the amount of > confusion. > > Does anyone see an issue with doing this change?
You mean apart from people now filing bugs how var_dump() can output
such a nonsensical number from such an easy equation? And that it again
shows that PHP is not a real programming language (unlike JavaScript)
and should never be used at all?
Nope ;-)
Cheers
Andreas
PS: I'd absolutely appreciate the change!!!
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