3 Ruby Tools For Newbies

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If you're new to programming in Ruby, here are the 3 tools you must know.

Debugger
The Ruby debugging tool can be found in the library file debug.rb. This tool will let you run your program one instruction at a time, with pauses in between. At every pause you can examine the values or variables of your code, locate your position in a series of nested commands and/or resume execution. You can also tell the debugger when to stop, more commonly known as breakpoints.

Using a debugger varies from programmer to programmer. Just because a debugging facility is available for Ruby, it doesn't mean that a novice programmer should quickly adapt himself to using it at once. There are programmers who are comfortable using a debugger, some aren't. It's a matter of preference but at any rate, it's nice to know that there's a tool available for Ruby.

Profiling
Eventually, when you start writing longer programs, you'll want to measure how much resources, especially time, is used up by parts of your program or as a whole. This is called profiling.

You can do profiling using the command $ ruby -r profile myfile.rb
Profiling identifies the areas in your program that are using up lots of the system resources. Having identified these areas, you need to re-code your program to make it run efficiently.

ERb
Probably the coolest tool of them all, Ruby provides you with a program called ERb (Embedded Ruby), which allows you to put Ruby code inside an HTML file. You get to embed Ruby inside non-Ruby, and interprets the whole thing as program input.



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