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Rust Requires Chilkat v11.4.0+

Eval JavaScript Returning Int

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Demonstrates getting the completion value of a JavaScript that returns an integer.

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Rust

// This example demonstrates getting the completion value of a script,
// where the last evaluated expression is an integer.

// The Javascript run in this example is shown below.

// Load the JavaScript from a file.
let sb_script = chilkat::StringBuilder::new();
if sb_script.load_file("js_eval_return_int.js", "utf-8").is_err() {
    println!("{}", sb_script.last_error_text());
    return;
}

let js = chilkat::Js::new();
let result = chilkat::JsonObject::new();

// Run the JavaScript
// Eval returns the completion value of the script. This is generally the value of the last evaluated expression.
// In this case, the last evaluated expression is an int.
if js.eval(&sb_script, &result).is_err() {
    println!("{}", sb_script.last_error_text());
    return;
}

result.set_emit_compact(false);
println!("{}", result.emit().unwrap_or_default());

// Output:

// {
//   "type": "int",
//   "value": 42
// }
JavaScript
const base = 10;
const multiplier = 4;
const offset = 2;

// The last line is a calculation resulting in an integer
// Returns 42.
(base * multiplier) + offset;