expected64 is a tagged union to hold double, int64_t, uint64_t, and (64-bit) pointers.
The core idea is to use a single bit to indicate an Error type in a union such as this:
union
{
T value;
E error;
};
A user must check if the error bit is set by first calling has_error(). Please see the tests for more details but the expected flow is of the nature:
auto result = some_function(some_value);
if (result.has_error()) // error handing
else // result.get_value()
Each of the four supported types are handled slightly differently.
Doubles use the bits only after the quiet_NaN() nan mask to store error info.
| Bit | 63 | 62-52 | 51-0 |
|---|---|---|---|
| Use | S | 11111111111 | Non-zero fraction (not all zeros) |
Ran locally on a i7-14700
| ns/op | op/s | err% | ins/op | cyc/op | IPC | bra/op | miss% | total | benchmark |
|---|---|---|---|---|---|---|---|---|---|
| 2.12 | 471,147,691.07 | 1.6% | 38.00 | 7.19 | 5.287 | 10.25 | 0.0% | 0.03 | factorial-raw-int |
| 2.94 | 340,087,470.50 | 4.0% | 54.00 | 10.05 | 5.373 | 11.25 | 0.0% | 0.04 | factorial-optional-int |
| 2.80 | 356,678,076.01 | 2.1% | 53.00 | 9.46 | 5.600 | 11.25 | 0.0% | 0.04 | factorial-tlexpected-int |
| 2.21 | 452,669,048.44 | 1.7% | 40.00 | 7.53 | 5.312 | 11.25 | 0.0% | 0.03 | factorial-expected64-int |
See the BUILDING document.
See the CONTRIBUTING document.
MIT License
Copyright (c) [2024] [Josh G]
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