smpallen99
Debugging a pipeline with IO.inspect/2
Did you know that IO.inspect/2 returns the the first argument and accepts a label option as a second argument. This makes it a perfect tool to logging intermediate results in a pipeline, as well as intermediate results in a function. Take the following pipeline, for example:
def get_gifts(santa, wishlist, snack) do
santa
|> receives_wishlist(wishlist)
|> leaves_presents
|> eats(snack)
|> wakeup_to
end
Now lets say that you don’t get your gifts. Try the following:
def get_gifts(santa, wishlist, snack) do
santa
|> receives_wishlist(wishlist)
|> IO.inspect(label: "after wishlist received")
|> leaves_presents()
|> IO.inspect(label: "after presents")
|> eats(snack)
|> wakeup_to()
|> IO.inspect(label: "result")
end
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voger
I think there is a bug in your code. You should pattern match for :naughty or :nice or something. That’s why the gift doesn’t get delivered.
Sorry for the offtopic. I couldn’t resist. ![]()
smpallen99
I would love to see it implemented for logger too. I’ve been burned a couple times with at :ok return value.
NobbZ
Indeed a very nice feature! And on the issue tracker there is even a discussion about making this possible for Logger calls as well…
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