existance | management tool for eXist-db instances | Continuous Deployment library

I'm not really sure advantage you hope to gain by marking a rule terminal... unless I'm missing something it doesn't seem to have much to do with what you want to do.

Your final problem ("a rule fails because the file didn't exist"), by which I understand you to mean the uninstall recipe fails, is simple enough to fix: just set RM = rm -f so that rm won't fail if the file doesn't exist.

It would be great if you could give an example of what you really want to do; how you expect to invoke make and how you want it to behave (resulting operations).

Make is designed to update files, not delete files. That is, its whole goal is to find files that don't exist or are out of date, and make them exist / update them.

However, you could do something like this:

Add the required data to pass on the element directly via data-attributes for $(".sid").val() will only ever get you the value of the first element based on the html you supplied.

When the first value is always the one being passed, it is expected that your checks on your backend will notify you that the record already existed.

You can change your markup to this:

For the file copying (and not folder copying, if I understood correctly within your question's context) you can just use the copyToLocalFile method from FileSystem as seen here by specifying the boolean that checks if you want to delete the source file, and the input (HDFS)/output (local) paths.

As for the periodic checking of the existence of the file in HDFS, you can use a ScheduledExecutorService object (Java 8 docs here) by specifying that you want your functions' execution to run every 5 minutes.

The following program takes two arguments, the path of the input file in the HDFS and the path of the output file locally.

Problem is after I log out, the app crashes:

The compiler doesn't know as much as you. It can't know that you've already checked that the file exists (and, of course, the file could be deleted in between the existence check and use).

You should indicate to the compiler (and readers) that things are really broken if you reach that point. A standard way to do this would be something like:

Simply:

• have a mutex associated with each object,
• keep each object in a smart pointer,
• keep smart pointers in some concurrent map (e.g. Intel's TBB one).

Usage:

• someone gets the pointer from the map (safe),
• while holding a smart pointer reference to the object tries to lock the mutex (safe),
• uses the object and subsequently releases the lock (safe),
• disposes the local smart pointer copy (safe).

When it's time to delete the object:

• you remove it from the map (safe),
• the object is destroyed after the last reference to it is disposed of (safe).

If I were to remove the line which substracts the balance, the tokens would only appear on the receivers balance, but the senders balance would not change.

That's correct.

If that happens the total tokens in existance would be more than before.

Correct for the total sum of existing tokens.

But - The token standards (ERC-20, ERC-721, etc.) also expect you to calculate the total amount of existing tokens (usually stored in a property named totalSupply). Since your snippet doesn't update this totalSupply, its value would became untrue.

The total supply is mostly used by blockchain explorers such as Etherscan for statistical purposes (calculating the largest holders of a token, their ownership percentage, etc.).

Other systems, such as decentralized exchanges or dapps in general, might behave unexpectedly when the totalSupply() output doesn't match the real total supply. But it all depends on their implementation, so there's no general answer.

To prevent users from accidentally overwriting each other's data, you'll want to use a transaction.

To prevent users from intentionally overwriting each other's data, you'll want to use security rules. Key to this is to use the information that you want to be unique as the ID of the documents.

So say you identify time slots by the date and start time, you could have a document ID "20210420T0900". If a user is trying to write to that document when it already exists, you can reject that write in the security rules of your database.

You cannot update a cytoscape.js style currently.

There are 2 ways in my mind. The best is to use a function style