00_hello/index.html

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        <li>00 Hello</li>
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    <h1>hello</h1>
    <div class="content"><div class="rspec_file">  <div class="intro"><h1>Hello!</h1>

<p>This lab teaches basic Ruby function syntax.</p>

<h2>Open a terminal in this directory</h2>

<pre><code>cd 00_hello
</code></pre>

<p>This directory is the starting point for this exercise. It contains a spec file and a ruby file to (eventually) make the specs pass.</p>

<h2>Run the test</h2>

<pre><code>rake
</code></pre>

<h2>Watch it fail</h2>

<p>you should see an error like this:</p>

<pre><code>the hello function
  says hello (FAILED - 1)

Failures:

  1) the hello function says hello
     Failure/Error: expect(hello).to eq("Hello!")
     NameError:
       undefined local variable or method `hello' for #&lt;RSpec::Core::ExampleGroup::Nested_1:0x000001009b8808&gt;
     # ./hello/hello_spec.rb:5:in `block (2 levels) in &lt;top (required)&gt;'
</code></pre>

<h2>Create the hello function</h2>

<p>Fix this by opening <code>hello.rb</code> and creating an empty function:</p>

<pre><code>def hello
end
</code></pre>

<p>Save it. Run the test again.</p>

<h2>Watch it fail</h2>

<p>Now you should see an error like this:</p>

<pre><code>the hello function
  says hello (FAILED - 1)

Failures:

  1) the hello function says hello
     Failure/Error: expect(hello).to eq("Hello!")
       expected: "Hello!"
            got: nil (compared using ==)
     # ./hello/hello_spec.rb:5:in `block (2 levels) in &lt;top (required)&gt;'
</code></pre>

<p>This means that while it found the file, and it found the function, it's not returning anything! ("nil" is the Ruby way of saying "not anything".)</p>

<h2>Make it return something</h2>

<p>Inside the "hello" function, put a single line containing a string that is <em>not</em> "Hello!". (Here we are simulating you making an honest mistake, so we can see what the error message looks like.)</p>

<pre><code>def hello
  "whuh?"
end
</code></pre>

<p>Save it. Run the test again.</p>

<h2>Watch it fail</h2>

<p>Now you should see an error like this:</p>

<pre><code>1) the hello function says hello
   Failure/Error: expect(hello).to eq("Hello!")
     expected: "Hello!"
          got: "whuh?" (compared using ==)
   # ./hello/hello_spec.rb:5:in `block (2 levels) in &lt;top (required)&gt;'
</code></pre>

<p>Correct this by changing "whuh?" to "Hello!". Save it. Run the test again.</p>

<h2>Watch it pass!</h2>

<p>Hooray! Finally! It works!</p>

<h2>Give yourself a high five</h2>

<p>Also, sing a song and do a little dance.</p>

<h2>And then...</h2>

<p>Fix the next failure! <code>:-)</code></p>

<pre><code>the hello function
  says hello

the greet function
  says hello to someone (FAILED - 1)
</code></pre>

<p>In order to get the next test to pass, your function will need to accept an <em>argument</em>.</p>

<pre><code>def greet(who)
  "Hello, #{who}!"
end
</code></pre>
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  <div class="tests">
    <h1>Tests</h1>
<a class="raw_file" href="hello_spec.rb">hello_spec.rb</a>
    <pre>require &quot;hello&quot;

describe &quot;the hello function&quot; do
  it &quot;says hello&quot; do
    expect(hello).to eq(&quot;Hello!&quot;)
  end
end

describe &quot;the greet function&quot; do
  it &quot;says hello to someone&quot; do
    expect(greet(&quot;Alice&quot;)).to eq(&quot;Hello, Alice!&quot;)
  end

  it &quot;says hello to someone else&quot; do
    expect(greet(&quot;Bob&quot;)).to eq(&quot;Hello, Bob!&quot;)
  end
end</pre>
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