scala

If you ever need to write some Scala (or Java) code where you add a JSON string to the body of an HTTP POST request, here's a quick example of how to do it using the Apache HttpClient library methods:

Just a quick note here that I'm developing a simple shell script to build a Scala SBT project directory structure. Here's the shell script in its current incarnation:

In a little bit of accidental Scala REPL fun this afternoon, I was testing a recursive algorithm like the following simple factorial algorithm, and forgot a return statement:

def factorial(n: Int):Int = {
  if (n == 1) n    // forgot 'return' here
  factorial(n - 1)
}

When I pasted that code into the Scala REPL and then tried to test it as shown below, it didn't come back for a while, until it failed with this error message:

Okay, this is pretty cool. With sbt, you can magically refer to dependencies that are set up as GitHub projects, and those projects don't need to have a jar file, they can just be a source code library. This means you can save your Scala libraries as source code to GitHub (like you normally would), then pull them into your other Scala projects simply by referencing them in your build.sbt file.

Assuming you're comfortable with sbt, here's a quick six-step example that shows how to pull a GitHub library into a simple Scala project:

UPDATE: This example shows how to create an implicit method in Scala 2.9 or older. You can use a slightly simpler approach with Scala 2.10 and newer, which I've documented in this Scala 2.10 implicit class example.

I'm not going to do much writing here today, but instead I'll just demonstrate how an implicit method argument works with implicit fields in Scala. Without any further ado, here's some code: