added new sample to add predicate get_time/1 #338
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| // Check if the input arguments are of the types you expected. | ||
| _, ok := env.Resolve(TimeStamp).(engine.Variable) | ||
| if !ok { | ||
| return engine.Error(engine.TypeError(engine.NewAtom("variable"), TimeStamp, env)) |
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They removed type_error(variable, Culprit) from the standard in ISO/IEC 13211-1:1995/Cor.2:2012 and replaced it with uninstantiation_error(Culprit).
see https://www.complang.tuwien.ac.at/ulrich/iso-prolog/error_k#error_classes
Another predicate design I often see is to think Timestamp can be an integer but you can leave it as a variable. Let's say we call get_time(1735657200) at the right time. It should succeed, right? If you missed the timing, it fails. A variable should work fine too but for anything else, type_error(integer, Culprit).
You don't have to follow these in your get_time/1 but I prefer the ISO Prolog way in the examples.
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@ichiban, afais, the uninstantiation_error(Culprit) error term isn’t available in the repo. Do you think it would be a useful addition?
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If it adds no value to the existing examples, I'll close it. |
Folks,
in case you're interested I added a new example to implement get_time(-Timestamp).
Feel free to add it if you think is useful.
Roger.