Documentation directives

Crystal also provides several directives that inform the documentation generator how it should treat documentation for a specific feature. These include the following:

• :ditto:
• :nodoc:
• :inherit:

Let's take a closer look at what they do.

Ditto

The :ditto: directive can be used to copy the documentation from the previous definition, like so:

# Returns the number of items within this collection.
def size; end
 
# :ditto:
def length; end
 
# :ditto:
#
# Some information specific to this method.
def count; end

When the documentation is generated, #length would have the same sentence as #size. #count would also have this sentence, in addition to another sentence that's specific to that method. This can help reduce duplication for a series of related methods.

Nodoc

Documentation is only generated for the public API. This means that private and protected features are hidden by default. However, in some cases, a type...