| lib.rs |
A JEXL evaluator written in Rust
This crate depends on a JEXL parser crate that handles all the parsing
and is a part of the same workspace.
JEXL is an expression language used by Mozilla, you can find more information here: https://github.com/mozilla/mozjexl
# How to use
The access point for this crate is the `eval` functions of the Evaluator Struct
You can use the `eval` function directly to evaluate standalone statements
For example:
```rust
use jexl_eval::Evaluator;
use serde_json::json as value;
let evaluator = Evaluator::new();
assert_eq!(evaluator.eval("'Hello ' + 'World'").unwrap(), value!("Hello World"));
```
You can also run the statements against a context using the `eval_in_context` function
The context can be any type that implements the `serde::Serializable` trait
and the function will return errors if the statement doesn't match the context
For example:
```rust
use jexl_eval::Evaluator;
use serde_json::json as value;
let context = value!({"a": {"b": 2.0}});
let evaluator = Evaluator::new();
assert_eq!(evaluator.eval_in_context("a.b", context).unwrap(), value!(2.0));
```
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