Most languages are fairly easy to be productive with in a day and master in a few weeks if you already have lots of experience. Some languages are more complicated than others, and the domains they are used for might require a lot more work to learn and master if you are unfamiliar with them.
A language like Haskell or Rust might take much longer to master depending on where you are coming from.
When I was an undergrad, we had a "language of the week"-style PL class. It seemed like an easy 4.0 given the languages they covered (mid-90s, so it was Smalltalk, Prolog, Lisp, SML, and a few more I can't recall).
A language like Haskell or Rust might take much longer to master depending on where you are coming from.
When I was an undergrad, we had a "language of the week"-style PL class. It seemed like an easy 4.0 given the languages they covered (mid-90s, so it was Smalltalk, Prolog, Lisp, SML, and a few more I can't recall).