Struct exprtk_rs::Expression

pub struct Expression { /* fields omitted */ }

Methods

impl Expression

pub fn new(string: &str, symbols: SymbolTable) -> Result<Expression, ParseError>

Compiles a new Expression. Missing variables will lead to a exprtk::ParseError.

Example:

The above example melts down to this:

use exprtk_rs::*;

let mut symbol_table = SymbolTable::new();
symbol_table.add_variable("a", 2.).unwrap();
let expr = Expression::new("a + 1", symbol_table).unwrap();
assert_eq!(expr.value(), 3.);

pub fn with_vars(     string: &str,     symbols: SymbolTable ) -> Result<(Expression, Vec<(String, usize)>), ParseError>

Compiles a new Expression. Missing variables are automatically added to the SymbolTable and initialized with 0.. Their names and IDs are returned as tuple together with the Expression instance.

pub fn value(&self) -> c_double

Calculates the value of the expression. Returns NaN if the expression was not yet compiled.

pub fn symbols(&mut self) -> &mut SymbolTable

Trait Implementations

impl Send for Expression

impl Drop for Expression

fn drop(&mut self)

Executes the destructor for this type.

impl Debug for Expression

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

Formats the value using the given formatter.

impl Clone for Expression

fn clone(&self) -> Expression

Returns a copy of the value.

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

Performs copy-assignment from source.