[−][src]Struct evalexpr::Node

pub struct Node { /* fields omitted */ }

A node in the operator tree. The operator tree is created by the crate-level build_operator_tree method. It can be evaluated for a given context with the Node::eval method.

The advantage of constructing the operator tree separately from the actual evaluation is that it can be evaluated arbitrarily often with different contexts.

Examples

use evalexpr::*;

let mut context = HashMapContext::new();
context.set_value("alpha", 2).unwrap(); // Do proper error handling here
let node = build_operator_tree("1 + alpha").unwrap(); // Do proper error handling here
assert_eq!(node.eval_with_context(&context), Ok(Value::from(3)));

Methods

`impl Node`[src]

`pub fn eval_with_context(&self, context: &dyn Context) -> EvalexprResult<Value>`[src]

Evaluates the operator tree rooted at this node with the given context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval(&self) -> EvalexprResult<Value>`[src]

Evaluates the operator tree rooted at this node with an empty context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_string_with_context( &self, context: &dyn Context ) -> EvalexprResult<String>`[src]

Evaluates the operator tree rooted at this node into a string with an the given context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_float_with_context( &self, context: &dyn Context ) -> EvalexprResult<FloatType>`[src]

Evaluates the operator tree rooted at this node into a float with an the given context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_int_with_context( &self, context: &dyn Context ) -> EvalexprResult<IntType>`[src]

Evaluates the operator tree rooted at this node into an integer with an the given context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_number_with_context( &self, context: &dyn Context ) -> EvalexprResult<FloatType>`[src]

Evaluates the operator tree rooted at this node into a float with an the given context. If the result of the expression is an integer, it is silently converted into a float.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_boolean_with_context( &self, context: &dyn Context ) -> EvalexprResult<bool>`[src]

Evaluates the operator tree rooted at this node into a boolean with an the given context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_tuple_with_context( &self, context: &dyn Context ) -> EvalexprResult<TupleType>`[src]

Evaluates the operator tree rooted at this node into a tuple with an the given context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_string(&self) -> EvalexprResult<String>`[src]

Evaluates the operator tree rooted at this node into a string with an empty context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_float(&self) -> EvalexprResult<FloatType>`[src]

Evaluates the operator tree rooted at this node into a float with an empty context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_int(&self) -> EvalexprResult<IntType>`[src]

Evaluates the operator tree rooted at this node into an integer with an empty context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_number(&self) -> EvalexprResult<FloatType>`[src]

Evaluates the operator tree rooted at this node into a float with an empty context. If the result of the expression is an integer, it is silently converted into a float.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_boolean(&self) -> EvalexprResult<bool>`[src]

Evaluates the operator tree rooted at this node into a boolean with an empty context.

Fails, if one of the operators in the expression tree fails.

`pub fn eval_tuple(&self) -> EvalexprResult<TupleType>`[src]

Evaluates the operator tree rooted at this node into a tuple with an empty context.

Fails, if one of the operators in the expression tree fails.

Trait Implementations

`impl Debug for Node`[src]

`fn fmt(&self, f: &mut Formatter) -> Result`[src]

`impl Display for Node`[src]

`fn fmt(&self, f: &mut Formatter) -> Result<(), Error>`[src]

Auto Trait Implementations

`impl !Send for Node`

`impl !Sync for Node`

Blanket Implementations

`impl<T> From for T`[src]

`fn from(t: T) -> T`[src]

`impl<T, U> Into for T where U: From<T>,` [src]

`fn into(self) -> U`[src]

`impl<T> ToString for T where T: Display + ?Sized,` [src]

`fn to_string(&self) -> String`[src]

`impl<T, U> TryFrom for T where U: Into<T>,` [src]

`type Error = Infallible`

The type returned in the event of a conversion error.

`fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>`[src]

`impl<T> Borrow for T where T: ?Sized,` [src]

`fn borrow(&self) -> &T`[src]

`impl<T> Any for T where T: 'static + ?Sized,` [src]

`fn type_id(&self) -> TypeId`[src]

`impl<T> BorrowMut for T where T: ?Sized,` [src]

`fn borrow_mut(&mut self) -> &mut T`[src]

`impl<T, U> TryInto for T where U: TryFrom<T>,` [src]

`type Error = <U as TryFrom<T>>::Error`

The type returned in the event of a conversion error.

`fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>`[src]