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45 lines
1.1 KiB
Markdown
45 lines
1.1 KiB
Markdown
# Return The Thing Being Printed
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The [`puts`](https://ruby-doc.org/core-3.0.2/Kernel.html#method-i-puts) method
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is the canonical way of priting things to stdout in Ruby. Notably, its return
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value is always `nil`. Generally this isn't much of an issue, but can be a
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potential gotcha while debugging.
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Consider the following method whose behavior you are trying to investigate:
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```ruby
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def process(arg)
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thing = do_something(arg)
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thing.value
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end
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```
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I want to print out the value of thing when I execute the code to see what it
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is while debugging. So I add a `puts` statement.
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```ruby
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def process(arg)
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thing = do_something(arg)
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puts thing.value
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end
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```
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Well, I just broke the behavior of `process` because it now returns `nil`
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instead of `thing.value`.
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I could add an additional line that returns the correct value. Or I could use
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[`p`](https://ruby-doc.org/core-3.0.2/Kernel.html#method-i-p) which both prints
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its argument to stdout and returns it as is.
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```ruby
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def process(arg)
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thing = do_something(arg)
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p thing.value
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end
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```
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[source](https://dev.to/lofiandcode/ruby-puts-vs-print-vs-p-vs-pp-vs-awesome-5akl)
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