Struct ParameterBuilder 

pub struct ParameterBuilder<'a, 's, T: ParameterVariant> { /* private fields */ }

Builder for declaring a typed parameter

Implementations

impl<'a, 's, T: ParameterVariant> ParameterBuilder<'a, 's, T>

pub fn new( server: &'a mut ParameterServer<'s>, node: NodeKey, name: &'a str, ) -> Self

Create a new parameter builder

pub fn default(self, value: T) -> Self

Set a default value for the parameter

The ONE default setter. rclrs also has default_from_iter(impl IntoIterator) and default_string_array(&[&str]); neither exists here, so pass the array value itself. An array is a heapless::Vec bounded by MAX_ARRAY_LEN (a string array is Vec<String<MAX_STRING_VALUE_LEN>, MAX_ARRAY_LEN>, two compile-time bounds), and an over-capacity value is refused by ParameterVariant::try_to_parameter_value, never truncated. No allocator.

pub fn description(self, desc: &'a str) -> Self

Set a human-readable description for the parameter

pub fn constraints(self, text: &'a str) -> Self

Set the free-text additional_constraints — rclrs’s ParameterBuilder::constraints, and rclc’s fourth argument to rclc_add_parameter_description (phase-417 W4.a).

Text longer than NROS_MAX_PARAM_CONSTRAINTS_LEN — whose default is 0, so an image pays for this field only when it asks for it — is truncated at a character boundary and REPORTED once through ParameterServer::take_truncated_descriptions, never dropped in silence.

pub fn integer_range( self, min: i64, max: i64, step: i64, ) -> Result<Self, ParameterError>

Set integer range constraints for the parameter

pub fn float_range( self, min: f64, max: f64, step: f64, ) -> Result<Self, ParameterError>

Set floating point range constraints for the parameter

pub fn range(self, range: RangeInclusive<T>) -> Result<Self, ParameterError>

where T: RangeConvertible,

Set range constraints using an inclusive range

This is a convenience method that works with RangeInclusive:

• For i64 parameters: range(0..=100) sets an integer range with step 1
• For f64 parameters: range(0.0..=1.0) sets a floating point range with step 0.0

For more control (e.g., custom step), use integer_range() or float_range().

pub fn read_only(self) -> Result<ReadOnlyParameter<'a, 's, T>, ParameterError>

Declare a read-only parameter

Read-only parameters cannot be changed after declaration. A default value must be provided.

pub fn mandatory(self) -> Result<MandatoryParameter<'a, 's, T>, ParameterError>

Declare a mandatory parameter

If no default value is provided, it must be set externally before use.

pub fn optional(self) -> Result<OptionalParameter<'a, 's, T>, ParameterError>

Declare an optional parameter