Generate markdown documentation also for none type

[christophfroehlich]

Closes #266

$ generate_parameter_library_markdown --input_yaml src/ros2_controllers/chained_filter_controller/src/chained_filter_parameters.yaml --output_markdown test.md

Before:

Chained Filter Parameters

Default Config

chained_filter:
  ros__parameters:
    input_interfaces: '{}'
    output_interfaces: '{}'

input_interfaces

Name of the input state interface

• Type: string_array
• Default Value: {}
• Read only: True

Constraints:

• parameter is not empty

Additional Constraints:

output_interfaces

Name of the output state interface

• Type: string_array
• Default Value: {}
• Read only: True

Constraints:

• parameter is not empty

Additional Constraints:

After:

Chained Filter Parameters

Default Config

chained_filter:
  ros__parameters:
    <input_interfaces>:
      filter_chain: ''
    filter_chain: ''
    input_interfaces: '{}'
    output_interfaces: '{}'

input_interfaces

Name of the input state interface

• Type: string_array

• Default Value: {}

• Read only: True

Constraints:

• parameter is not empty

Additional Constraints:

output_interfaces

Name of the output state interface

• Type: string_array

• Default Value: {}

• Read only: True

Constraints:

• parameter is not empty

Additional Constraints:

filter_chain

Map of parameters that defines a filter chain, containing filterN as key. Valid for all interfaces, overrides <input_interfaces>.filter_chain if set. The fields for each filter are: type: The filter plugin to be loaded name: Actual name semantically describing the filter, e.g., low_pass_filter params: And underlying map of parameters needed for a specific filter, refer to the specific filter documentation.

<input_interfaces>.filter_chain

Instead of a single configuration, a distinct configuration can be provided for each input interface. The key is the name of the input interface, and the value is a map of parameters that defines a filter chain, containing filterN as key. The fields for each filter are: type: The filter plugin to be loaded name: Actual name semantically describing the filter, e.g., low_pass_filter params: And underlying map of parameters needed for a specific filter, refer to the specific filter

[bmagyar]

thank you!