Clarify meaning of floating point m.room.power_levels

[velikopter]

Not sure if I did this the right way..

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Signed-off-by: Kierre Sametti vel@riseup.net

Preview: https://pr2297--matrix-spec-previews.netlify.app

[richvdh]

I see we already have a section about stringy power levels. Is it the case that strings representing floats are accepted here too? In other words, are "5.17" and "1.34E3" accepted?

If so, we should probably combine the two sections into a single "m.room.power_levels events accept values as strings or floats" section.

If not, we could do with a clarification in the stringy power levels section.

[velikopter]

floating-point powerlevels aren't allowed in strings:

>>> int("5.63")
Traceback (most recent call last):
  File "<python-input-1>", line 1, in <module>
    int("5.63")
    ~~~^^^^^^^^
ValueError: invalid literal for int() with base 10: '5.63'
>>> 

I will add a clarification in that section.

[velikopter]

I believe this is already described well:

a single base 10 integer, no float values or decimal points, optionally with any number of leading zeroes ("100", "000100");

(emphasis mine)

[richvdh]

Right, yes.

I think the bit that's confusing me is the words "When the value is representative of an integer", which makes it sound like we haven't decided what to if the string contains something that isn't an integer.

I think it should probably say something like:

For fields where the schema for m.room.power_levels specifies an integer, a string complying with the following rules is also permitted:

[richvdh]

(Thanks for taking this on!)

[richvdh]

Related: #1244

[richvdh]

Question: how is a power level of 99.999999999999999 handled?

Or, since we're talking edge cases, 1e400 ?

[velikopter]

Question: how is a power level of 99.999999999999999 handled?

Or, since we're talking edge cases, 1e400 ?

>>> int(1e400)
Traceback (most recent call last):
  File "<python-input-0>", line 1, in <module>
    int(1e400)
    ~~~^^^^^^^
OverflowError: cannot convert float infinity to integer
>>> int(99.999999999999999)
100
>>>