Struct Expression 

pub struct Expression { /* private fields */ }

A FHIRPath expression, parsed.

Implementations

impl Expression

pub fn parse(text: &str) -> Result<Self, ParseError>

Parses text.

Errors

Returns ParseError when text is no N1 expression.

pub fn source(&self) -> &str

The text the expression was parsed from.

pub const fn tree(&self) -> &Expr

The syntax tree.

pub fn check( &self, model: &dyn Model, context: FhirType, ) -> Result<(), SemanticError>

Checks the expression against the type its context will have: every member a path names must be one the types along the path define, and a path that starts with a type name must start with the context’s (N1 §3, §11).

Errors

Returns SemanticError for the first member or type name the model refuses.

pub fn check_any( &self, model: &dyn Model, contexts: &[FhirType], ) -> Result<(), SemanticError>

Checks the expression against a context that may hold any of the types contexts, as an occurrence of a choice element does (R4 §2.9.1.1, crate::model::path_types): a member is accepted when one of them defines it, and refused when none does.

Errors

Returns SemanticError for the first member or type name the model refuses.

pub fn evaluate<'a>( &self, env: &Environment<'a>, focus: Focus<'a>, ) -> Result<Collection<'a>, EvalError>

Evaluates the expression in env on focus.

Errors

Returns EvalError when the evaluation signals an error; an empty result is Ok with an empty collection.

Trait Implementations

impl Clone for Expression

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Expression

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

Formats the value using the given formatter.

impl Display for Expression

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

Formats the value using the given formatter.

impl Eq for Expression

impl FromStr for Expression

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(text: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl PartialEq for Expression

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Expression