launch.launch_description_source module
Module for the LaunchDescriptionSource class.
- class launch.launch_description_source.LaunchDescriptionSource[source]
Bases:
object
Encapsulation of a launch description, where it comes from, and how it was generated.
- __init__(launch_description: LaunchDescription | None = None, location: str | Substitution | Iterable[str | Substitution] = '<string>', method: str = 'unspecified mechanism from a script') None [source]
Create a LaunchDescriptionSource.
For example, loading a file called
example.launch.py
for inclusion might end up setting location to/path/to/example.launch.py
and themethod
to beinterpreted python launch file
.- Parameters:
launch_description – the launch description that this source represents
location – the location from where this launch description was loaded if applicable
method – the method by which the launch description was generated
- get_launch_description(context: LaunchContext) LaunchDescription [source]
Get the LaunchDescription, loading it if necessary.
- property location: str
Get the location of the launch description source as a string.
The string is either a list of Substitution instances converted to strings or the expanded path if
get_launch_description()
has been called.
- try_get_launch_description_without_context() LaunchDescription | None [source]
Attempt to load the LaunchDescription without a context, return None if unsuccessful.
This method is useful for trying to introspect the included launch description without visiting the user of this source.