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2 comments:

• Patchset:

  • Patch Set #2:

    Thanks for review and merging.

• File src/target/trx_toolkit/data_msg.py:

  • Patch Set #2, Line 31: struct.unpack('b', struct.pack('B', x))[0]

    Alternatively, we could use `int.to_bytes()` / `int.from_bytes()` API here: […]

    Performance does not matter here at all as _bu2s is used only at import time to construct `_tab_sbit2usbit` and `_tab_sbit2ubit` tables.

    But anyway here is performance comparision of this two approaches:

    ```
    In [2]: def _bu2s(x):
       ...:     return struct.unpack('b', struct.pack('B', x))[0]
       ...: 

    In [3]: def V_bu2s(x): return int.from_bytes(x.to_bytes(1), signed=True)

    In [6]: _bu2s(0x81)
    Out[6]: -127

    In [7]: V_bu2s(0x81)
    Out[7]: -127

    In [8]: %timeit _bu2s(0x81)
    137 ns ± 1.21 ns per loop (mean ± std. dev. of 7 runs, 10,000,000 loops each)

    In [9]: %timeit V_bu2s(0x81)
    162 ns ± 1.42 ns per loop (mean ± std. dev. of 7 runs, 10,000,000 loops each)
    ```

    so struct-based variant works a bit faster.

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