Commenting and Documentation in Ruby and Rails

It’s always been frustrating to me that Ruby and Rails don’t really have strong templated standards on how to best document your code. There are several options available and it can all be very confusing and unclear.

There is one template I’ve found works best and its super simple:

# Brief explanation of what the code does.
#
# * *Args* :
# - ++ ->
# * *Returns* :
# -
# * *Raises* :
# - ++ ->
def my_method

end

While there are many other perfectly good documentation libraries this has the benefits of being simple to remember, very easy to read in code, and compiles out super nicely using

rake doc:app

Example (strongly based off this post):

# This is an example method commented the way I 
# like. It sums the three arguments and returns 
# that value.
#
# Lorem ipsum dolor sit amet, consectetur adipising,
# do eiusmod tempor incididunt ut labore et dolore. 
# Ut enim ad minim veniam, quis nostrud exercit
# laboris nisi ut aliquip ex ea commodo consequat.
#
# * *Args* :
#   - +apples+ -> the number of apples
#   - +oranges+ -> the number of oranges
#   - +pears+ -> the number of pears
# * *Returns* :
#   - the total number of fruit as an integer
# * *Raises* :
#   - +ArgumentError+ -> if any value is nil or negative
def sum_fruit(apples, oranges, pears)
  ...
end

Will render into something like this:


Other than this, I tend to try and follow the general conventions as outlined by the Rails contribution guidelines on commenting.

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