What are some disadvantages (real and potential)?ĭevelopers cannot be 100% certain that all arguments sent this empty? method will have a size method that is publicly accessible. That ruby program use less code and are more flexible. What does this say about the advantages of ruby's dynamic (duck) typed system? The ruby method accepts any Object and could return anything, but in this case will return a boolean if executed without exceptions. The Java method only accepts Strings as arguments and only returns a boolean while. The primary way to achieve this is to assert that the actual result of the method matches an expected result. Strong candidates will argue that it allows a developer to flesh out their API before it's consumed by other systems in the application. Unit testing, simply put, is testing methods - the smallest unit in object-oriented programming. The strongest candidates should be quite comfortable with test or behavior driven development. #=> But what about me? #=> I'm a block, but could it be? #=> # What is unit testing (in classical terms)? What is the primary technique when writing a test?

In reality: classes hold data, have methods that interact with that data, and are used to instantiate objects.Ĭlass WhatIsSelf def test puts 'At the instance level, self is # three_ways ( anonymous, nameless ) do puts 'I'm a block, but could it be?' end #=> I'm a Proc for sure.

What is a class?Ī text-book answer: classes are a blue-print for constructing computer models for real or virtual objects. Senior programmers won't have a problem with these, while junior programmers will usually give only half-answers. Especially during an interview, when your mouth goes dry and and your hands get all sweaty. But it does provide a useful tool to put a candidate's reaction to the same series of questions in perspective. Make no mistake, this list is not complete, by any means. Candidates get my respect for knowing esoteric solutions, but I'm looking for developers with similar practices to my own. There are many solutions to most of these questions - some aren't listed here. So it's up to you to decide the correctness of their answer. What to expectĬandidates will typically give you a range of responses based on their experience and personality. To ensure we hired competent ruby developers at my last job, I created a list of 15 ruby questions - a ruby measuring stick if you will - to select the cream of the crop that walked through our doors. And in the corporate/enterprise world, I often don't have access to their previous work. In 30 minutes or less, it's difficult to get a solid read on a candidate's skill set without looking at code they've previously written. When hiring Ruby on Rails programmers, knowing the right questions to ask during an interview was a real challenge for me at first.

Cerner interview questions github