unsafe integer passed to Big constructor when using .sqrt() / option to throw for unsafe ints

[danday74]

big.js line 780:

r = new Big(s);

Here, s is potentially an unsafe integer when square rooting numbers larger than Number.MAX_SAFE_INTEGER^2

A safer op might be:

r = new Big(s + '');

Please close if no fix is needed, but I wanted to point this out. I am throwing if the Big.js constructor is passed an unsafe integer.

Would be great if big.js had a toggle option to throw in this scenario. As it currently stands, precision can be accidentally lost when doing Big(Number.MAX_SAFE_INTEGER + 1) - I appreciate a string can be passed in this occasion but as a developer, it is easy to accidentally pass an unsafe int and miss it.

[MikeMcl]

It doesn't matter if s is an unsafe integer, and turning it into a string is not necessary - that happens anyway in the Big constructor.

Regarding whether to have an option to throw on unsafe integers generally, that is not something I want to add to this library. It is available in bignumber.js I think.

[danday74]

ok

shame about not adding the option - bignumber.js much slower than this lib

I've had to create https://www.npmjs.com/package/big.js.safe as a workaround :(

[MikeMcl]

Okay, but it may be misleading to call the package "safe" as precision can still easily be lost when non-integer JavaScript numbers are passed

new Big(1.0000000000000001);    // '1'
new Big(88259496234518.57);     // '88259496234518.56'
new Big(1e-324);                // '0'