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Comment by habibur | Hacker News Reader

Look at C++ as a scripting language and you possibly will not dislike it as much.

Agreed! I use C++ for small scripts/tools and love it. Granted, I first spent some time writing a library of convenience functions like starts_with(), ends_with(), contains(), get_file_contents(), read_csv_file(), etc. that so many languages have built into their standard libraries, but to be honest, even that part was a lot of fun!

CERN actually does that with CLING for interactive HEP data science.

https://root.cern/cling/

Thanks!

  $ brew install cling
  $ cling
   
  ****************** CLING ******************
  * Type C++ code and press enter to run it *
  *             Type .q to exit             *
  *******************************************
  [cling]$ #include <stdio.h>
  [cling]$ #include <sys/utsname.h>
  [cling]$ struct utsname u;
  [cling]$ uname(&u);
  [cling]$ printf("%s %s %s\n", u.sysname, u.release, u.machine);
  Darwin 20.5.0 arm64

You can even use it interactively like ipython and get rid of the printf, as it automatically evaluates expressions.

  [cling]$ int i=21
  (int) 21
  [cling]$ i*2
  (int) 42

Thanks! Is there a way to see strings nicely without printf?

  [cling]$ u.sysname
  (char [256]) "Darwin\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"

I imagine if you printed an actual string it would look as you expect, issue is that you're printing a char array and not a C++ std::string/_view

Sure, but I’d expect the interpreter to have some smarts to do the right thing within reason.

But a char[] could be binary data for all the tool knows, do you want it to do a buffer overflow and end up bricking your computer? std::string etc. exist exactly because char[] is unsafe for holding strings unless you carry around a size.

There is a size in the example I posted above.

  [cling]$ u.sysname
    (char [256])

Indeed, this is the expected behavior with C arrays, regardless their type.

The solutions are either to use a C++ std::string as you mentioned, or a typedef struct with a length property.

struct utsname is what it is. For me the appeal for something like cling would be doing quick experiments without any boilerplate.

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