Using rlwrap with MIT's Scheme REPL

Users of the Linux or OS X command line know that they can hit the up arrow to view the previously executed command. However, this behavior is missing from the mit-scheme read-evaluate-print-loop (REPL). mit-scheme is the language used in SICP.

For example, hitting the up arrow in the Scheme REPL gives us this non-useful result: ^[[A. The previous command is not repeated.

How do we add up-arrow functionality to the mit-scheme REPL? By using rlwrap.

Apple Car? Not Likely.

You have to figure out what your own aptitudes are. If you play games where other people have the aptitudes and you don’t, you’re going to lose. And that’s as close to certain as any prediction that you can make. You have to figure out where you’ve got an edge. And you’ve got to play within your own circle of competence.

~Charlie Munger, Vice Chairman, Berkshire Hathaway

Some journalists speculate that Apple is building a car because they recently hired some automotive engineers away from Tesla.

HTML5 & CSS3: The Complete Manual

The biggest challenge for a software developer: Absorbing the latest knowledge while simultaneously keeping clients happy. Where does the time go?

Fortunately, when it comes to HTML5 and CSS3, a UK-based publisher has released a just-the-facts guide that may help. At 127 pages, the entire publication (they call it a bookazine) can be devoured in a single day. Imagine Publishing’s HTML5 & CSS3: The Complete Manual is well worth the time investment.

Note: A version of this article also appears in the Book Reviews section of ChicagoRuby.org.

JRuby 9000 on Mac OS X

Moore’s Law is about to run into a wall. Therefore, anything that software developers can learn about concurrency will be critical in coming years. Enter JRuby 9000.

Raspberry Pi 2 Model B Quad Core

The Raspberry Pi Foundation has upped their entry in the single-board computer competition. Raspberry Pi 2 Model B boasts a quad core ARM CPU and 1GB of RAM. More important: Benchmarks show that the board is 6x faster than the previous model. And the performance bump has been achieved while the price remains low: Roughly $45.

Getting the board up and running is easier, too. You can buy a pre-built Linux image on micro SD. Or you can download the New Out Of the Box (NOOBS) image yourself. Depending on the speed of your internet connection, you can be up in running in less than an hour.