Function evaluate 

pub fn evaluate(value: &Value, scope: &Value) -> Value

Evaluates a config value against scope.

A string like "=item.name" (a simple dotted path) resolves that path within scope, with missing segments yielding Value::Null. Any other =-prefixed string is treated as a jq program run against scope (see the module docs), returning its first output or Value::Null. Non-expression values are returned as a literal clone.

Examples

use serde_json::json;
use tinyflows::expr::evaluate;

let scope = json!({ "user": { "name": "Ada" }, "nums": [1, 2, 3] });

// A simple dotted path walks the scope segment by segment.
assert_eq!(evaluate(&json!("=user.name"), &scope), json!("Ada"));

// A leading dot routes to the jq engine; here, the array length.
assert_eq!(evaluate(&json!("=.nums | length"), &scope), json!(3));

// A missing path yields null rather than erroring.
assert_eq!(evaluate(&json!("=user.email"), &scope), json!(null));

// Non-expression values pass through as a literal clone.
assert_eq!(evaluate(&json!("literal"), &scope), json!("literal"));
assert_eq!(evaluate(&json!(42), &scope), json!(42));