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Is this strictly a physical thing or can it apply in software?
> molly-guard: n.
> [University of Illinois] A shield to prevent tripping of some Big Red Switch by clumsy or ignorant hands. Originally used of the plexiglass covers improvised for the BRS on an IBM 4341 after a programmer's toddler daughter (named Molly) frobbed it twice in one day. Later generalized to covers over stop/reset switches on disk drives and networking equipment. In hardware catalogues, you'll see the much less interesting description “guarded button".
There is a Debian package with the same name that does the same thing: replaces shutdown and reboot scripts with ones that need an additional confirmation before you bring the machine down.
More people need to know about this. Every time I ask some software dev if he knows the term Poka Yoke the answer is always no. Same goes for many operations engineers. And when explained what it is, people assume it is the same as "idiot proof". No, it is not. Is a microwave door that turns the thing off when opened made for idiots? No, just regular people who want to use the microwave without frying their brain in…
It's true that you can benefit from idiot-proof design without being an idiot, but I would argue that you could market a microwave that doesn't turn off when you open the door, plastered with warnings and maybe a mandatory course on how to operate it. An idiot-proof version would have safeguards that everyone could benefit from, but then saying that it's a fundamentally different concept just seems needlessly combative.
Earlier quoted context omitted.
Pretty much all good software design practices exist to prevent mistakes by constraining behavior. It would be interesting to try and formalize it and make it more specifically analogous to what's in manufacturing.
A process (Failure Modes and Effects Analysis FMEA) used to arrive at eventual error proofing in manufacturing has existed since the 1940s. There have been attempts to bring this process over to software. A quick search shows attempts in the 1970s. I am really not sure why it hasn't caught on in software. I suppose the challenge is that you need to have specifications for what the outcome should be. In manufacturing…
In my ~ 20 year career, I hardly ever got a real specification for what should happen when things went right. It was very hard to get people to even acknowledge that things could go wrong, let alone specify what should happen in that case. Almost always, they'd suggest something should never go wrong, or we should fix whatever it was that was going wrong, etc. Which sure, that'd be nice, but really everything breaks, so what do you want me to do when it does?
Slightly different to what is described here, but one of my pet peeves is the "nuclear button" features that devs put in their software - ie easy to activate features that add marginal utility to specific niche workflows but cause irreversible damage to everyone else. Firefox deleting every single one of your pinned tabs on close if you have a second window open is an example of this, as is YouTube jumping to a diffe…
Hmm, I was always told to do so when I was learning to drive. At some point I stopped doing so and it’s never been an issue, should I be stepping on the brakes when starting my car?
Is this strictly a physical thing or can it apply in software?
Or perhaps the constructor pattern requiring object construction to complete before a reference to the object is available.
> some automatic transmissions require the brake pedal to be depressed [to start] Hmm, I was always told to do so when I was learning to drive. At some point I stopped doing so and it’s never been an issue, should I be stepping on the brakes when starting my car?
Most modern cars have a lockout, preventing you from starting the engine unless the brake (or clutch) is pressed. However, some older cars do not have this feature.
> some automatic transmissions require the brake pedal to be depressed [to start] Hmm, I was always told to do so when I was learning to drive. At some point I stopped doing so and it’s never been an issue, should I be stepping on the brakes when starting my car?