Skip to main content

Documentation Index

Fetch the complete documentation index at: https://mintlify.com/Crane04/esem/llms.txt

Use this file to discover all available pages before exploring further.

Not everything in a Python module is a function. Module-level variables — strings, numbers, booleans, dicts, lists, and None — are exposed on the module proxy as awaitable properties. Each access triggers a get_attr RPC call to the Python worker, which reads the attribute value, serializes it, and returns it to JavaScript. The result is deserialized automatically into the equivalent native JS type.

​
Defining constants in Python

# config.py
VERSION = "1.0.0"
SETTINGS = {
    "debug": True,
    "ports": [3000, 3001],
}

​
Reading constants from JavaScript

Await the property access on the module proxy to retrieve the value: 
import { python } from "esem-bridge";

const config = await python("./config.py");

console.log(await config.VERSION);  // "1.0.0"
console.log(await config.SETTINGS); // { debug: true, ports: [3000, 3001] }

​
Destructuring constants

When you destructure a non-callable export, the destructured binding itself is a Promise. Await it when you need the value: 
const { VERSION } = await python("./config.py");

console.log(await VERSION); // "1.0.0"
Each property access on a non-callable attribute sends a fresh get_attr RPC to the Python worker. If you read the same constant multiple times, store the resolved value in a local JS variable instead of awaiting the property repeatedly.
const version = await config.VERSION; // one RPC
console.log(version);                 // no RPC — just a local variable
console.log(version);

​
Type mapping reference

The test fixture (test/fixture.py) covers all supported constant types. The table below shows what each Python value becomes in JavaScript:
Python constantPython typeJavaScript valueJavaScript type
VERSION = "0.1.2"str"0.1.2"string
ENABLED = Truebooltrueboolean
RETRY_COUNT = 3int3number
NOTHING = NoneNoneTypenullnull
SETTINGS = {...}dict{ debug: true, ports: [...] }object
These are verified by the integration test suite: 
const fixture = await python("./test/fixture.py");

assert.equal(await fixture.VERSION, "0.1.2");
assert.equal(await fixture.ENABLED, true);
assert.equal(await fixture.RETRY_COUNT, 3);
assert.equal(await fixture.NOTHING, null);
assert.deepEqual(await fixture.SETTINGS, {
  debug: true,
  ports: [3000, 3001],
});
Functions and classes are not accessed this way. When the bridge loads a module it inspects every public attribute: callables become async JS functions (or class proxies), and only non-callable values become awaitable properties. If you try to await a function proxy as though it were a plain value, you will receive the function itself, not a return value.

Build docs developers (and LLMs) love

Get started for freeTalk to us