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Differences from json-logic-js

At the time of writing, json-logic-engine is 100% compatible with json-logic-js's test suite

However, in order to switch to fully compatible behaviors, you must pass a flag into the constructor.

const engine = new LogicEngine(undefined, { compatible: true })

This will make minor modifications to truthiness rules. In the future, I will likely make this the default behavior.

Empty Arrays are Truthy​

By default, empty arrays are truthy in json-logic-engine while they are falsy in json-logic-js. This is likely due to JSON Logic's roots in PHP.

"all" with zero items evaluates to true​

To keep in line with JavaScript's every method by default, json-logic-engine checks if each item in an array checked against a conditional is true, if there are zero items in the array the method defaults to true.

{
    "all": [[], { "var": "" }]
} 
// json-logic-js: false
// json-logic-engine: true