puts debugging

puts debugging is the time-honored practice of tracking down a bug by scattering puts statements through your code to print out values as it runs, then reading the output to see where things went wrong. puts is Ruby’s plainest way to print a line of text to the screen (it is short for “put string”), so puts user.name simply shows you what user.name actually is at that moment. It is the low-tech alternative to a full step-through debugger, and it is beloved partly because Ruby’s own Aaron Patterson ("tenderlove") (Aaron Patterson, a longtime Ruby and Rails core contributor) has cheerfully championed it. In a 2016 post titled “I am a puts debuggerer,” he wrote: “I am a puts debuggerer. I don’t say this to disparage people that use a Real Debugger. I think Real Debuggers are great, I’ve just never taken the time to learn one well.” If you have ever solved a problem this way and felt a little sheepish, take heart: you are in very good company.

Related: Aaron Patterson ("tenderlove")