maximum Integer value

When we use a variable to store an Integer, is there a maximum on the Espruino board? The official maximum for Javascript is 2^53, but I don't know if this holds up for the Espruino.

Furthermore, is there a performance maximum? I would assume that smaller numbers are more efficient since they are easier to represent and can fit in one register. Up to what maximum number would performance be best?

Finally, I assume that the chars in a String range from 0-255? I looked through the reference, but I could not find any description of how to use Unicode chars so I assume those are not supported?

Hi Kim,

• Number range: Espruino uses 64 bit integers wherever possible (so +/- 2^63), however as soon as you start doing floating point stuff (even 100/50) it'll drop back to doubles, where 2^53 is probably the limit before you lose accuracy.

• Performance: The overhead of parsing is really much higher than that of maths, so (at least at the moment) you're unlikely to notice a big difference whatever numbers you use. Trying to stick to integer values will probably help though (you can coerce doubles into integers using | - eg. x=x|0.

• Unicode: yes, characters in Strings are only 8 bits - so if you want to do Unicode you'll have to use UTF-8. Espruino itself is completely unaware though, which could make life tricky.