reval 0.6.6

Simple Rust expression evaluator
Documentation 
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//! This example shows how to pass in Decimal values and how to use them in a rule
//! This is a bit of a workaround/hack

use reval::prelude::*;
use rust_decimal::Decimal;
use serde::Serialize;

#[tokio::main]
async fn main() {
    // Pass in a data-type containing a Decimal field
    #[derive(Serialize)]
    struct Data {
        amount: Decimal,
    }

    // Set up a simple rule that passes the decimal value out without change
    let rule = r#"
    {
        "name": "pass decimal",
        "expr": { "gt": [
            {"cdecimal": {"ref": "amount"}},
            {"decimal": 900}
        ]}
    }"#;

    // Set up the ruleset builder, add the rule and build the `RuleSet`
    let ruleset = ruleset()
        .with_rule(Rule::parse_json(rule).unwrap())
        .unwrap()
        .build();

    // Set up input data
    let facts = Data {
        amount: Decimal::new(1000, 0),
    };

    // Evaluate the ruleset on the input data and check if the rule returns
    // `false`
    for outcome in ruleset.evaluate(&facts).await.unwrap() {
        assert_eq!(outcome.value.unwrap(), Value::String("11".to_string()));
    }
}