usb-device-cdc: optmise CDCInterface constructor - #1138
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dpgeorge
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Jul 15, 2026
| cdc = CDCInterface() | ||
| cdc.init(timeout=0) # zero timeout makes this non-blocking, suitable for os.dupterm() | ||
| # Zero timeout makes this non-blocking, suitable for os.dupterm(). | ||
| cdc = CDCInterface(timeout=0) |
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We don't have to make this change, but I thought it was a little cleaner to set the timeout in the constructor.
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@projectgus curious what you think about this change? I can close the PR if you don't think it's a good idea. |
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Jul 29, 2026
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Looks like a nice optimisation to me!
Don't set instance attributes that will just be reset by `self.init()`. Saves 30 bytes of bytecode. Signed-off-by: Damien George <damien@micropython.org>
Makes the example a little bit simpler. Signed-off-by: Damien George <damien@micropython.org>
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Summary
Don't set
CDCInterfaceinstance attributes that will just be reset byself.init().Saves 30 bytes of bytecode.
Also simplify the associated example.
Testing
Built, and tested the example on RPI_PICO. It still works.
Trade-offs and Alternatives
This makes it less clear what exactly are the instance attributes, because their initialisation is done in
.init(), not the constructor. The added comment tries to work around that.Generative AI
Not used.