- Variables 4:48
- Variables and Methods 4 objectives
- Attribute Readers 1:46
- Attribute Readers 1 objective
- Attribute Writers and Accessors 5:20
- Attribute Writers and Accessors 2 objectives
- Methods 3:31
- Methods 1 objective
- Instance Variables and Local Variables 4:54
- Instance Variables and Local Variables 4 questions
- The to_s method 2:16
- The to_s Method 1 objective
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The to_s method
2:16A common idiom that Ruby programmers use when writing classes is to define a `to_s` method, which tells Ruby how to print out a class.
A common idiom that Ruby programmers use
when writing classes and
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instances is to use the to_s method.
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This method is a convention, and
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is called by Ruby when an object wants to
be formatted as a string.
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Let's see how that works now with the name
class using workspaces.
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Okay, so here's our name class and
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it's just like before except I took out
the attribute reader for
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first and middle name and put it back to
what we have before with full name.
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Now let's take a look at what happens when
we print out just the name so
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I'm gonna write ruby name.rb.
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And we see that we get this funny little
format right here,
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which is the name of the class and its
address in memory.
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Whenever we print something out to the
screen using the puts method,
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internally Ruby is calling to string on it
or to_s.
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And we can override that in our classes if
we want to.
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So if we look here, we've got this to_s
method.
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And let's just have this print out the
full name with the title.
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Now when to_s is called is should print
out the full name.
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And there we go.
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It can be very useful when you're working
with your own classes to
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define a to_s method.
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Another method that we could use if we
wanna find out
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a little bit more about the object we're
working with is the inspect method.
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Inspect will tell you the internal state
of the object that you’re working with.
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So here we can see the same thing as
before, it’s the name class.
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And the place in memory or the object ID.
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And we also have a listing of all of the
internal instance variables
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of the class as well as their values.
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