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I have been willing to try Julia for a long time now. Yesterday I finally put time aside to port some stuff I have been doing in Python to Julia. 1st: install

by wtdata 7y ago

I have been willing to try Julia for a long time now. Yesterday I finally put time aside to port some stuff I have been doing in Python to Julia. 1st: install Julia - used a snap on Ubuntu, fine 2nd: get jupyter to work with Julia: a bit complex, but achievable 3rd: install Julia support for vscode: Julia kernel keeps crashing in vscode 4th: Port a routine from Python to Julia: some nice language features, some scary: importing a package exposes all its functions to the all namespace - this seems quite awful! (EDIT: Thank you for pointing out that I should use `import` instead of `use`, in order not to put everything in the same namespace). 5th: Try to read a Parquet file - doesn't work because it was compressed with zstd (something all 3 libraries for parquet in Python support) 6th: realize that there is no package in Julia that even allows to write parquet files Conclusion: maybe in a few years Julia will be my go-to language, but right now, it's too underdeveloped in order to be able to do real work with it.

ChrisRackauckas 7y ago
Use import instead of using if you don't want things in your namespace.
- wtdata 7y ago
  Ah, thank you! That was a very rookie mistake from my part then.
StefanKarpinski 7y ago
As Chris said, `using` is mostly for interactive usage where having to import each name you use is annoying. If you want to import specific names, do `import SomePackage: name1, name2`. When doing `using SomePackage` it only imports the names that are explicitly exported by `SomePackage`. Even collisions don't cause problems very often because exported type names tend to be fairly unique and when two packages use the same name for a function, there's a strong chance it's actually the same generic function shared between the packages so there's no collision. When that's not the case and the name is fairly generic, e.g. `connect`, then it's quite common to use the API as `SomePackage.connect` rather than as just `connect`. This is quite a bit different from class-based object-oriented languages, so it takes a little while to get used to. The issues with Parquet files are likely to get sorted out in the near future (a few months), so try again soon.

by wtdata 7y ago

ChrisRackauckas 7y ago

Use import instead of using if you don't want things in your namespace.

wtdata 7y ago
Ah, thank you! That was a very rookie mistake from my part then.

StefanKarpinski 7y ago

As Chris said, `using` is mostly for interactive usage where having to import each name you use is annoying. If you want to import specific names, do `import SomePackage: name1, name2`. When doing `using SomePackage` it only imports the names that are explicitly exported by `SomePackage`. Even collisions don't cause problems very often because exported type names tend to be fairly unique and when two packages use the same name for a function, there's a strong chance it's actually the same generic function shared between the packages so there's no collision. When that's not the case and the name is fairly generic, e.g. `connect`, then it's quite common to use the API as `SomePackage.connect` rather than as just `connect`. This is quite a bit different from class-based object-oriented languages, so it takes a little while to get used to. The issues with Parquet files are likely to get sorted out in the near future (a few months), so try again soon.