python

`python` is a built-in global object for running Python code from Expr.

It is used directly by name. Do not call `python()`.

Methods

Evaluates a Python expression string and returns the converted result.

value = python.eval('2 + 3 * 5');
print(value);        // 17

Runs Python code synchronously and returns the Python script result.

result = python.run_code('result = 40 + 2');
print(result);       // 42

Runs Python code synchronously with parameters from a `map`.

result = python.run_code('result = a + b', map('a', 10, 'b', 20));
print(result);       // 30

Runs a Python file synchronously and returns the Python script result.

result = python.run_file('scripts/example.py');

Runs a Python file synchronously with parameters from a `map`.

result = python.run_file('scripts/example.py', map('a', 10, 'b', 20));

Creates a `python_task` object for asynchronous execution of Python code.

task = python.code('result = 7');
task.run();

Creates a `python_task` object for asynchronous Python code execution with parameters.

Creates a `python_task` object for asynchronous execution of a Python file.

Creates a `python_task` object for asynchronous Python file execution with parameters.

`python_task` is returned by `python.code(…)` and `python.file(…)`.

Properties:

Property	Type	Description
`started`	boolean	`true` after `run()` has been called.
`running`	boolean	`true` while the Python task is running.
`completed`	boolean	`true` after the task finishes.
`ok`	boolean	`true` when the task completed successfully.
`use_subinterpreter`	boolean	Current sub-interpreter setting.
`result`	any	Result returned by the Python script.
`error`	string or none	Error text when the task failed.
`event_count`	number	Number of queued events from Python.

Methods:

Method	Returns	Description
`on_complete(callback)`	boolean	Sets a callback called with `ok` and `result`.
`on_event(callback)`	boolean	Sets a callback called with event name and value.
`use_subinterpreter(enabled)`	boolean	Sets sub-interpreter use before `run()`.
`run()`	boolean	Starts the task. A task can be run only once.
`read_event()`	map or none	Reads the next queued event.
`send_command(name, value)`	boolean	Sends a command to the running Python script.
`terminate()`	boolean	Requests termination of the running Python script.

Example:

task = python.code('result = 123');
task.run();
while (!task.completed) {}
print(task.result);

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