Struct Context

pub struct Context { /* private fields */ }

Shared state between nodes and similar entities.

It is possible, but not usually necessary, to have several contexts in an application.

Ownership of the context is shared by the Context itself and all nodes created from it.

Details

A context stores, among other things

• command line arguments (used for e.g. name remapping)
• middleware-specific data, e.g. the domain participant in DDS
• the allocator used (left as the default by rclrs)

Implementations

impl Context

pub fn new(args: impl IntoIterator<Item = String>) -> Result<Self, RclrsError>

Creates a new context.

Usually, this would be called with std::env::args(), analogously to rclcpp::init(). See also the official “Passing ROS arguments to nodes via the command-line” tutorial.

Creating a context can fail in case the args contain invalid ROS arguments.

Example

assert!(Context::new([]).is_ok());
let invalid_remapping = ["--ros-args", "-r", ":=:*/]"].map(String::from);
assert!(Context::new(invalid_remapping).is_err());

pub fn ok(&self) -> bool

Checks if the context is still valid.

This will return false when a signal has caused the context to shut down (currently unimplemented).