Handling Overflow

[omus]

Currently a FixedDecimal value can overflow since internally we are using integer math.

julia> import FixedPointDecimals: FD

julia> reinterpret(FD{Int8,2}, typemax(Int8))
FixedDecimal{Int8,2}(1.27)

julia> ans + reinterpret(FD{Int8,2}, 1)
FixedDecimal{Int8,2}(-1.28)

We should include some kind of system, maybe checked_* operations, so that users can choose how overflow is handled. We definitely do not want to ban the overflow behaviour.

[TotalVerb]

Checked operations sound like a good idea to me, as that's consistent with how Ints work.

Also, there have been proposals in Base to have macros like @checked that rewrite a + b to checked_add(a, b), and so they would tie into any such implemented proposal well.

[DatName]

Would like to bump this issue. Just stumbled upon

julia>  FixedDecimal{Int64, 12}(1) * 10000000
FixedDecimal{Int64,12}(-8446744.073709551616)

which was unexpected for me.

[NHDaly]

#85