Struct cedar_policy_core::ast::ExtensionFunction

pub struct ExtensionFunction { /* private fields */ }

Extension function. These can be called by the given name in Ceder expressions.

Implementations

impl ExtensionFunction

pub fn nullary( name: Name, style: CallStyle, func: Box<dyn Fn() -> Result<ExtensionOutputValue, EvaluationError> + Sync + Send + 'static>, return_type: SchemaType, ) -> Self

Create a new ExtensionFunction taking no arguments

pub fn unary_never( name: Name, style: CallStyle, func: Box<dyn Fn(Value) -> Result<ExtensionOutputValue, EvaluationError> + Sync + Send + 'static>, arg_type: Option<SchemaType>, ) -> Self

Create a new ExtensionFunction taking one argument, that never returns a value

pub fn unary( name: Name, style: CallStyle, func: Box<dyn Fn(Value) -> Result<ExtensionOutputValue, EvaluationError> + Sync + Send + 'static>, return_type: SchemaType, arg_type: Option<SchemaType>, ) -> Self

Create a new ExtensionFunction taking one argument

pub fn binary( name: Name, style: CallStyle, func: Box<dyn Fn(Value, Value) -> Result<ExtensionOutputValue, EvaluationError> + Sync + Send + 'static>, return_type: SchemaType, arg_types: (Option<SchemaType>, Option<SchemaType>), ) -> Self

Create a new ExtensionFunction taking two arguments

pub fn ternary( name: Name, style: CallStyle, func: Box<dyn Fn(Value, Value, Value) -> Result<ExtensionOutputValue, EvaluationError> + Sync + Send + 'static>, return_type: SchemaType, arg_types: (Option<SchemaType>, Option<SchemaType>, Option<SchemaType>), ) -> Self

Create a new ExtensionFunction taking three arguments

pub fn name(&self) -> &Name

Get the Name of the ExtensionFunction

pub fn style(&self) -> CallStyle

Get the CallStyle of the ExtensionFunction

pub fn return_type(&self) -> Option<&SchemaType>

Get the return type of the ExtensionFunction None represents the Never type.

pub fn arg_types(&self) -> &[Option<SchemaType>]

Get the argument types of the ExtensionFunction.

If any given argument type is not constant (function works with multiple SchemaTypes) then this will be None for that argument.

pub fn is_constructor(&self) -> bool

Returns true if this function is considered a “constructor”.

Currently, the only impact of this is that non-constructors are not accessible in the JSON format (entities/json.rs).

pub fn call(&self, args: &[Value]) -> Result<PartialValue, EvaluationError>

Call the ExtensionFunction with the given args

Trait Implementations

impl Debug for ExtensionFunction

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.