Struct Expression

pub struct Expression<'a> { /* private fields */ }

A compiled JMESPath expression.

The compiled expression can be used multiple times without incurring the cost of re-parsing the expression each time. The expression may be shared between threads if JMESPath is compiled with the sync feature, which forces the use of an Arc instead of an Rc for runtime variables.

Implementations

impl<'a> Expression<'a>

pub fn new<S>(expression: S, ast: Ast, runtime: &'a Runtime) -> Expression<'a>

where S: Into<String>,

Creates a new JMESPath expression.

Normally you will create expressions using either jmespatch::compile() or using a jmespatch::Runtime.

pub fn search<T: ToJmespath>(&self, data: T) -> Result<Rcvar, JmespathError>

Returns the result of searching data with the compiled expression.

The SearchResult contains a JMESPath Rcvar, or a reference counted Variable. This value can be used directly like a JSON object. Alternatively, Variable does implement Serde serialzation and deserialization, so it can easily be marshalled to another type.

pub fn as_str(&self) -> &str

Returns the JMESPath expression from which the Expression was compiled.

Note that this is the same value that is returned by calling to_string.

pub fn as_ast(&self) -> &Ast

Returns the AST of the parsed JMESPath expression.

This can be useful for debugging purposes, caching, etc.

Trait Implementations

impl<'a> Clone for Expression<'a>

fn clone(&self) -> Expression<'a>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for Expression<'a>

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

Formats the value using the given formatter.

impl<'a> Display for Expression<'a>

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

Shows the jmespath expression as a string.

impl<'a> PartialEq for Expression<'a>

fn eq(&self, other: &Expression<'_>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.