I'm trying to learn how to step through Ruby code (written by more experienced programmers) in order to improve my knowledge of Ruby. Problem is that I don't really know how to do it well. Googling the topic brought me to an about.com page on Ruby; I thought a higher quality more comprehensive answer should belong on StackOverflow, so if anyone can write an answer (with an example) for it, showing how a beginner can step through code to learn as much as possible about it, it'd be much appreciated.
closed as off topic by Walter, ElYusubov, MainMa, GlenH7, Yannis Rizos♦ Oct 22 '12 at 18:42
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What you're looking for is a debugger. With ruby 1.8, the
Start your program with the gem loaded, for example
The debugger kicks in at a breakpoint, which is a signal to suspend execution, and give you a chance to poke around. Typically, the easiest way to set a breakpoint is to add a source line at the point in execution you're interested in. Inserting a call to
Lets launch it:
The program starts executing, then the debugger breaks us at line four. It shows us the next statement which is to be executed next. We can get a more complete listing of our surroundings by typing
You can examine the result of expressions by using the
The debugger has has interactive help which can be accessed with