Java API: Provide method for converting IDs to blank names

[mkroetzsch]

VLog's Java code currently transforms IDs val of null values into string names for blanks with the following code:
"" + (val >> 40) + "_" + ((val >> 32) & 0377) + "_" + (val & 0xffffffffL)
There is no documentation to clarify why it has to be this way, but if this is significant then it would be good to encapsulate it in a public method to enable callers to work with ids for null values. RuleWerk is currently replicating the code.

[CerielJacobs]

I don’t know if it is significant for users. It is this way because it helps in finding out where the blank comes from: (val >> 40) gives a rule number, ((val >> 32) & 0377) gives a variable number, (val & 0xffffffffL) is a counter.

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On 17 Jun 2020, at 22:17, Markus Krötzsch ***@***.***> wrote: VLog's Java code currently transforms IDs val of null values into string names for blanks with the following code: "" + (val >> 40) + "_" + ((val >> 32) & 0377) + "_" + (val & 0xffffffffL) There is no documentation to clarify why it has to be this way, but if this is significant then it would be good to encapsulate it in a public method to enable callers to work with ids for null values. RuleWerk is currently replicating the code. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or unsubscribe.

[mkroetzsch]

Thanks for the explanation. So at least there is no danger of breaking anything if VLog should at some point change its encoding and Rulewerk still has this code as it is now. Then maybe we can just keep the code as it is.

I don't know if the rule and variable number are really interpretable on our side, since there are rewritings happening (already in Rulewerk to bypass the EDB/IDB separation restrictions in VLog), so the internal numbers may not match the rules that the user sees.