pyodide.ffi#

Exceptions:

ConversionError

An error thrown when conversion between JavaScript and Python fails.

JsException

A wrapper around a JavaScript Error to allow it to be thrown in Python.

Classes:

JsArray()

A JsProxy of an array, node list, or typed array

JsAsyncGenerator()

A JavaScript async generator

JsAsyncIterable()

A JavaScript async iterable object

JsBuffer()

A JsProxy of an array buffer or array buffer view

JsDoubleProxy()

A double proxy created with create_proxy.

JsFetchResponse()

JsGenerator()

A JavaScript generator

JsIterable()

A JavaScript iterable object

JsIterator()

A JsProxy of a JavaScript iterator.

JsMap()

A JavaScript Map

JsMutableMap()

A JavaScript mutable map

JsPromise()

A JsProxy of a promise (or some other awaitable JavaScript object).

JsProxy()

A proxy to make a JavaScript object behave like a Python object

JsTypedArray()

Functions:

create_once_callable(obj, /)

Wrap a Python callable in a JavaScript function that can be called once.

create_proxy(obj, /, *[, capture_this, ...])

Create a JsProxy of a PyProxy.

destroy_proxies(pyproxies, /)

Destroy all PyProxies in a JavaScript array.

register_js_module(name, jsproxy)

Registers jsproxy as a JavaScript module named name.

to_js(obj, /, *[, depth, pyproxies, ...])

Convert the object to JavaScript.

unregister_js_module(name)

Unregisters a JavaScript module with given name that has been previously registered with pyodide.registerJsModule or pyodide.ffi.register_js_module.
exception pyodide.ffi.ConversionError#

Bases: Exception

An error thrown when conversion between JavaScript and Python fails.

class pyodide.ffi.JsArray#

Bases: pyodide.ffi.JsProxy, Generic[T]

A JsProxy of an array, node list, or typed array

append(object: .T) → None#

Append object to the end of the list.

count(x: .T) → int#

Return the number of times x appears in the list.

extend(other: collections.abc.Iterable[.T]) → None#

Extend array by appending elements from the iterable.

index(value: .T, start: int = 0, stop: int = 9223372036854775807) → int#

Return first index of value.

Raises ValueError if the value is not present.

pop(index: int = - 1) → T#

Remove and return item at index (default last).

Raises IndexError if list is empty or index is out of range.

reverse() → None#

Reverse the array in place.

Present only if the wrapped Javascript object is an array.

to_py(*, depth: int = - 1, default_converter: Optional[collections.abc.Callable[[JsProxy, collections.abc.Callable[[JsProxy], Any], collections.abc.Callable[[JsProxy, Any], None]], Any]] = None) → list[Any]#

Convert the JsProxy to a native Python object as best as possible.

By default, does a deep conversion, if a shallow conversion is desired, you can use proxy.to_py(depth=1). See JavaScript to Python for more information.

default_converter if present will be invoked whenever Pyodide does not have some built in conversion for the object. If default_converter raises an error, the error will be allowed to propagate. Otherwise, the object returned will be used as the conversion. default_converter takes three arguments. The first argument is the value to be converted.

Here are a couple examples of converter functions. In addition to the normal conversions, convert Date to datetime:

from datetime import datetime
def default_converter(value, _ignored1, _ignored2):
    if value.constructor.name == "Date":
        return datetime.fromtimestamp(d.valueOf()/1000)
    return value

Don’t create any JsProxies, require a complete conversion or raise an error:

def default_converter(_value, _ignored1, _ignored2):
    raise Exception("Failed to completely convert object")

The second and third arguments are only needed for converting containers. The second argument is a conversion function which is used to convert the elements of the container with the same settings. The third argument is a “cache” function which is needed to handle self referential containers. Consider the following example. Suppose we have a Javascript Pair class:

class Pair {
    constructor(first, second){
        this.first = first;
        this.second = second;
    }
}

We can use the following default_converter to convert Pair to list:

def default_converter(value, convert, cache):
    if value.constructor.name != "Pair":
        return value
    result = []
    cache(value, result);
    result.append(convert(value.first))
    result.append(convert(value.second))
    return result

Note that we have to cache the conversion of value before converting value.first and value.second. To see why, consider a self referential pair:

let p = new Pair(0, 0);
p.first = p;

Without cache(value, result);, converting p would lead to an infinite recurse. With it, we can successfully convert p to a list such that l[0] is l.

class pyodide.ffi.JsAsyncGenerator#

Bases: pyodide.ffi.JsAsyncIterable[Tco], Generic[Tco, Tcontra, Vco]

A JavaScript async generator

A JavaScript object is treated as an async generator if it’s Symbol.typeTag is AsyncGenerator. Most likely this will be because it is a true async generator produced by the JavaScript runtime, but it may be a custom object trying hard to pretend to be an async generator. It should have next, return, and throw methods.

aclose() → Awaitable[None]#

Raises a GeneratorExit at the point where the generator function was paused.

If the generator function then exits gracefully, is already closed, or raises GeneratorExit (by not catching the exception), close returns to its caller. If the generator yields a value, a RuntimeError is raised. If the generator raises any other exception, it is propagated to the caller. close() does nothing if the generator has already exited due to an exception or normal exit.

asend(value: .Tcontra) → Awaitable[.Tco]#

Resumes the execution and “sends” a value into the async generator function.

The value argument becomes the result of the current yield expression. The awaitable returned by the asend() method will return the next value yielded by the generator or raises StopAsyncIteration if the asynchronous generator returns. If the generator returned a value, this value is discarded (because in Python async generators cannot return a value).

When asend() is called to start the generator, the argument will be ignored. Unlike in Python, we cannot detect that the generator hasn’t started yet, and no error will be thrown if the argument of a not-started generator is not None.

athrow(type, value, traceback)#

Resumes the execution and raises an exception at the point where the generator was paused.

The awaitable returned by the asend() method will return the next value yielded by the generator or raises StopAsyncIteration if the asynchronous generator returns. If the generator returned a value, this value is discarded (because in Python async generators cannot return a value). If the generator function does not catch the passed-in exception, or raises a different exception, then that exception propagates to the caller.

class pyodide.ffi.JsAsyncIterable#

Bases: pyodide.ffi.JsProxy, Generic[Tco]

A JavaScript async iterable object

A JavaScript object is async iterable if it has a Symbol.asyncIterator method.

class pyodide.ffi.JsBuffer#

Bases: pyodide.ffi.JsProxy

A JsProxy of an array buffer or array buffer view

assign(rhs: Any, /) → None#

Assign from a Python buffer into the JavaScript buffer.

assign_to(to: Any, /) → None#

Assign to a Python buffer from the JavaScript buffer.

from_file(file: Union[IO[bytes], IO[str]], /) → None#

Reads from a file into a buffer.

Will try to read a chunk of data the same size as the buffer from the current position of the file.

Example

>>> import pytest; pytest.skip()
>>> from js import Uint8Array
>>> # the JsProxy need to be pre-allocated
>>> x = Uint8Array.new(range(10))
>>> with open('file.bin', 'rb') as fh:
...    x.read_file(fh)
which is equivalent to
>>> x = Uint8Array.new(range(10))
>>> with open('file.bin', 'rb') as fh:
...    chunk = fh.read(size=x.byteLength)
...    x.assign(chunk)
but the latter copies the data twice whereas the former only copies the
data once.
to_bytes() → bytes#

Convert a buffer to a bytes object.

Copies the data once.

to_file(file: Union[IO[bytes], IO[str]], /) → None#

Writes a buffer to a file.

Will write the entire contents of the buffer to the current position of the file.

Example

>>> import pytest; pytest.skip()
>>> from js import Uint8Array
>>> x = Uint8Array.new(range(10))
>>> with open('file.bin', 'wb') as fh:
...    x.to_file(fh)
which is equivalent to,
>>> with open('file.bin', 'wb') as fh:
...    data = x.to_bytes()
...    fh.write(data)
but the latter copies the data twice whereas the former only copies the
data once.
to_memoryview() → memoryview#

Convert a buffer to a memoryview.

Copies the data once. This currently has the same effect as to_py.

to_string(encoding: Optional[str] = None) → str#

Convert a buffer to a string object.

Copies the data twice.

The encoding argument will be passed to the Javascript [TextDecoder](https://developer.mozilla.org/en-US/docs/Web/API/TextDecoder) constructor. It should be one of the encodings listed in the table here: https://encoding.spec.whatwg.org/#names-and-labels. The default encoding is utf8.

class pyodide.ffi.JsDoubleProxy#

Bases: pyodide.ffi.JsProxy

A double proxy created with create_proxy.

unwrap() → Any#

Unwrap a double proxy created with create_proxy into the wrapped Python object.

exception pyodide.ffi.JsException#

Bases: Exception

A wrapper around a JavaScript Error to allow it to be thrown in Python. See Errors.

property js_error: pyodide.ffi.JsRawException#

The original JavaScript error

class pyodide.ffi.JsFetchResponse#

Bases: pyodide.ffi.JsProxy

class pyodide.ffi.JsGenerator#

Bases: pyodide.ffi.JsIterable[Tco], Generic[Tco, Tcontra, Vco]

A JavaScript generator

A JavaScript object is treated as a generator if it’s Symbol.typeTag is Generator. Most likely this will be because it is a true generator produced by the JavaScript runtime, but it may be a custom object trying hard to pretend to be a generator. It should have next, return, and throw methods.

close() → None#

Raises a GeneratorExit at the point where the generator function was paused.

If the generator function then exits gracefully, is already closed, or raises GeneratorExit (by not catching the exception), close returns to its caller. If the generator yields a value, a RuntimeError is raised. If the generator raises any other exception, it is propagated to the caller. close() does nothing if the generator has already exited due to an exception or normal exit.

send(value: .Tcontra) → Tco#

Resumes the execution and “sends” a value into the generator function.

The value argument becomes the result of the current yield expression. The send() method returns the next value yielded by the generator, or raises StopIteration if the generator exits without yielding another value. When send() is called to start the generator, the argument will be ignored. Unlike in Python, we cannot detect that the generator hasn’t started yet, and no error will be thrown if the argument of a not-started generator is not None.

throw(type, value, traceback)#

Raises an exception at the point where the generator was paused, and returns the next value yielded by the generator function.

If the generator exits without yielding another value, a StopIteration exception is raised. If the generator function does not catch the passed-in exception, or raises a different exception, then that exception propagates to the caller.

In typical use, this is called with a single exception instance similar to the way the raise keyword is used.

For backwards compatibility, however, the second signature is supported, following a convention from older versions of Python. The type argument should be an exception class, and value should be an exception instance. If the value is not provided, the type constructor is called to get an instance. If traceback is provided, it is set on the exception, otherwise any existing __traceback__ attribute stored in value may be cleared.

class pyodide.ffi.JsIterable#

Bases: pyodide.ffi.JsProxy, Generic[Tco]

A JavaScript iterable object

A JavaScript object is iterable if it has a Symbol.iterator method.

class pyodide.ffi.JsIterator#

Bases: pyodide.ffi.JsProxy, Generic[Tco]

A JsProxy of a JavaScript iterator.

An object is a JsIterator if it has a next method and either has a Symbol.iterator or has no Symbol.asyncIterator.

class pyodide.ffi.JsMap#

Bases: pyodide.ffi.JsProxy, Generic[KT, VTco]

A JavaScript Map

To be considered a map, a JavaScript object must have a .get method, it must have a .size or a .length property which is a number (idiomatically it should be called .size) and it must be iterable.

get(key, default=None)#

If key in self, returns self[key]. Otherwise returns default.

Present if the wrapped JavaScript object is a Mapping (i.e., has get, has, size, and keys methods).

items() → collections.abc.ItemsView[.KT, .VTco]#

Return a ItemsView for the map.

Present if the wrapped JavaScript object is a Mapping (i.e., has get, has, size, and keys methods).

keys() → collections.abc.KeysView[.KT]#

Return a KeysView for the map.

Present if the wrapped JavaScript object is a Mapping (i.e., has get, has, size, and keys methods).

values() → collections.abc.ValuesView[.VTco]#

Return a ValuesView for the map.

Present if the wrapped JavaScript object is a Mapping (i.e., has get, has, size, and keys methods).

class pyodide.ffi.JsMutableMap#

Bases: pyodide.ffi.JsMap[KT, VT], Generic[KT, VT]

A JavaScript mutable map

To be considered a mutable map, a JavaScript object must have a .get method, a .has method, a .size or a .length property which is a number (idiomatically it should be called .size) and it must be iterable.

Instances of the JavaScript builtin Map class are JsMutableMap s. Also proxies returned by JsProxy.as_object_map are instances of JsMap .

clear() → None#

Empty out the map entirely.

Present if the wrapped JavaScript object is a MutableMapping (i.e., has get, has, size, keys, set, and delete methods).

pop(key, default=None)#

If key in self, return self[key] and remove key from self. Otherwise returns default.

Present if the wrapped JavaScript object is a MutableMapping (i.e., has get, has, size, keys, set, and delete methods).

popitem() → tuple[KT, KT]#

Remove some arbitrary key, value pair from the map and returns the (key, value) tuple.

Present if the wrapped JavaScript object is a MutableMapping (i.e., has get, has, size, keys, set, and delete methods).

setdefault(key: .KT, default: typing.Optional[.VT] = None) → VT#

If key in self, return self[key]. Otherwise sets self[key] = default and returns default.

Present if the wrapped JavaScript object is a MutableMapping (i.e., has get, has, size, keys, set, and delete methods).

update(other, **kwargs)#

Updates self from other and kwargs.

If other is present and is a Mapping or has a keys method, does

for k in other:
    self[k] = other[k]

If other is present and lacks a keys method, does

for (k, v) in other:
    self[k] = v

In all cases this is followed by:

for (k, v) in kwargs.items():
    self[k] = v

Present if the wrapped JavaScript object is a MutableMapping (i.e., has get, has, size, keys, set, and delete methods).

class pyodide.ffi.JsPromise#

Bases: pyodide.ffi.JsProxy

A JsProxy of a promise (or some other awaitable JavaScript object).

A JavaScript object is considered to be a Promise if it has a “then” method.

catch(onrejected: collections.abc.Callable[[Any], Any], /) → pyodide.ffi.JsPromise#

The Promise.catch API, wrapped to manage the lifetimes of the handler.

Pyodide will automatically release the references to the handler when the promise resolves.

finally_(onfinally: collections.abc.Callable[[Any], Any], /) → pyodide.ffi.JsPromise#

The Promise.finally API, wrapped to manage the lifetimes of the handler.

Pyodide will automatically release the references to the handler when the promise resolves. Note the trailing underscore in the name; this is needed because finally is a reserved keyword in Python.

then(onfulfilled: collections.abc.Callable[[Any], Any], onrejected: collections.abc.Callable[[Any], Any]) → pyodide.ffi.JsPromise#

The Promise.then API, wrapped to manage the lifetimes of the handlers.

Pyodide will automatically release the references to the handlers when the promise resolves.

class pyodide.ffi.JsProxy#

Bases: object

A proxy to make a JavaScript object behave like a Python object

For more information see the Type translations documentation. In particular, see the list of __dunder__ methods that are (conditionally) implemented on JsProxy.

as_object_map() → pyodide.ffi.JsMutableMap[str, Any]#

Returns a new JsProxy that treats the object as a map.

The methods __getitem__, __setitem__, __contains__, __len__, etc will perform lookups via object[key] or similar.

Note that len(x.as_object_map()) evaluates in O(n) time (it iterates over the object and counts how many ownKeys it has). If you need to compute the length in O(1) time, use a real Map instead.

property js_id: int#

An id number which can be used as a dictionary/set key if you want to key on JavaScript object identity.

If two JsProxy are made with the same backing JavaScript object, they will have the same js_id. The reault is a “pseudorandom” 32 bit integer.

new(*args: Any, **kwargs: Any) → pyodide.ffi.JsProxy#

Construct a new instance of the JavaScript object

object_entries() → pyodide.ffi.JsProxy#

The JavaScript API Object.entries(object)

object_keys() → pyodide.ffi.JsProxy#

The JavaScript API Object.keys(object)

object_values() → pyodide.ffi.JsProxy#

The JavaScript API Object.values(object)

to_py(*, depth: int = - 1, default_converter: Optional[collections.abc.Callable[[JsProxy, collections.abc.Callable[[JsProxy], Any], collections.abc.Callable[[JsProxy, Any], None]], Any]] = None) → Any#

Convert the JsProxy to a native Python object as best as possible.

By default, does a deep conversion, if a shallow conversion is desired, you can use proxy.to_py(depth=1). See JavaScript to Python for more information.

default_converter if present will be invoked whenever Pyodide does not have some built in conversion for the object. If default_converter raises an error, the error will be allowed to propagate. Otherwise, the object returned will be used as the conversion. default_converter takes three arguments. The first argument is the value to be converted.

Here are a couple examples of converter functions. In addition to the normal conversions, convert Date to datetime:

from datetime import datetime
def default_converter(value, _ignored1, _ignored2):
    if value.constructor.name == "Date":
        return datetime.fromtimestamp(d.valueOf()/1000)
    return value

Don’t create any JsProxies, require a complete conversion or raise an error:

def default_converter(_value, _ignored1, _ignored2):
    raise Exception("Failed to completely convert object")

The second and third arguments are only needed for converting containers. The second argument is a conversion function which is used to convert the elements of the container with the same settings. The third argument is a “cache” function which is needed to handle self referential containers. Consider the following example. Suppose we have a Javascript Pair class:

class Pair {
    constructor(first, second){
        this.first = first;
        this.second = second;
    }
}

We can use the following default_converter to convert Pair to list:

def default_converter(value, convert, cache):
    if value.constructor.name != "Pair":
        return value
    result = []
    cache(value, result);
    result.append(convert(value.first))
    result.append(convert(value.second))
    return result

Note that we have to cache the conversion of value before converting value.first and value.second. To see why, consider a self referential pair:

let p = new Pair(0, 0);
p.first = p;

Without cache(value, result);, converting p would lead to an infinite recurse. With it, we can successfully convert p to a list such that l[0] is l.

property typeof: str#

Returns the JavaScript type of the JsProxy.

Corresponds to typeof obj; in JavaScript. You may also be interested in the constuctor attribute which returns the type as an object.

class pyodide.ffi.JsTypedArray#

Bases: pyodide.ffi.JsBuffer, pyodide.ffi.JsArray[int]

pyodide.ffi.create_once_callable(obj: collections.abc.Callable[[...], Any], /) → pyodide.ffi.JsOnceCallable#

Wrap a Python callable in a JavaScript function that can be called once.

After being called the proxy will decrement the reference count of the Callable. The JavaScript function also has a destroy API that can be used to release the proxy without calling it.

pyodide.ffi.create_proxy(obj: Any, /, *, capture_this: bool = False, roundtrip: bool = True) → pyodide.ffi.JsDoubleProxy#

Create a JsProxy of a PyProxy.

This allows explicit control over the lifetime of the PyProxy from Python: call the destroy API when done.

Parameters

  • obj (any) – The object to wrap.

  • capture_this (bool, default=False) – If the object is callable, should this be passed as the first argument when calling it from JavaScript.

  • roundtrip (bool, default=True) –

    When the proxy is converted back from JavaScript to Python, if this is True it is converted into a double proxy. If False, it is unwrapped into a Python object. In the case that roundtrip is True it is possible to unwrap a double proxy with the unwrap method. This is useful to allow easier control of lifetimes from Python:

    from js import o
d = {}
o.d = create_proxy(d, roundtrip=True)
o.d.destroy() # Destroys the proxy created with create_proxy

    With roundtrip=False this would be an error.

pyodide.ffi.destroy_proxies(pyproxies: pyodide.ffi.JsArray[Any], /) → None#

Destroy all PyProxies in a JavaScript array.

pyproxies must be a JsProxy of type PyProxy[]. Intended for use with the arrays created from the “pyproxies” argument of PyProxy.toJs and to_js. This method is necessary because indexing the Array from Python automatically unwraps the PyProxy into the wrapped Python object.

pyodide.ffi.register_js_module(name: str, jsproxy: Any) → None#

Registers jsproxy as a JavaScript module named name. The module can then be imported from Python using the standard Python import system. If another module by the same name has already been imported, this won’t have much effect unless you also delete the imported module from sys.modules. This is called by the JavaScript API pyodide.registerJsModule.

Parameters

  • name (str) – Name of js module

  • jsproxy (JsProxy) – JavaScript object backing the module

pyodide.ffi.to_js(obj: Any, /, *, depth: int = - 1, pyproxies: Optional[pyodide.ffi.JsProxy] = None, create_pyproxies: bool = True, dict_converter: Optional[collections.abc.Callable[[collections.abc.Iterable[pyodide.ffi.JsArray[Any]]], pyodide.ffi.JsProxy]] = None, default_converter: Optional[collections.abc.Callable[[Any, collections.abc.Callable[[Any], pyodide.ffi.JsProxy], collections.abc.Callable[[Any, pyodide.ffi.JsProxy], None]], pyodide.ffi.JsProxy]] = None) → Any#

Convert the object to JavaScript.

This is similar to PyProxy.toJs, but for use from Python. If the object can be implicitly translated to JavaScript, it will be returned unchanged. If the object cannot be converted into JavaScript, this method will return a JsProxy of a PyProxy, as if you had used pyodide.ffi.create_proxy.

See Python to JavaScript for more information.

Parameters

  • obj (Any) – The Python object to convert

  • depth (int, default=-1) – The maximum depth to do the conversion. Negative numbers are treated as infinite. Set this to 1 to do a shallow conversion.

  • pyproxies (JsProxy, default = None) – Should be a JavaScript Array. If provided, any PyProxies generated will be stored here. You can later use destroy_proxies if you want to destroy the proxies from Python (or from JavaScript you can just iterate over the Array and destroy the proxies).

  • create_pyproxies (bool, default=True) – If you set this to False, to_js will raise an error

  • dict_converter (Callable[[Iterable[JsProxy]], JsProxy], default = None) –

    This converter if provided receives a (JavaScript) iterable of (JavaScript) pairs [key, value]. It is expected to return the desired result of the dict conversion. Some suggested values for this argument:

    js.Map.new – similar to the default behavior js.Array.from – convert to an array of entries js.Object.fromEntries – convert to a JavaScript object

  • default_converter (Callable[[Any, Callable[[Any], JsProxy], Callable[[Any, JsProxy], None]], JsProxy], default=None) –

    If present will be invoked whenever Pyodide does not have some built in conversion for the object. If default_converter raises an error, the error will be allowed to propagate. Otherwise, the object returned will be used as the conversion. default_converter takes three arguments. The first argument is the value to be converted.

    Here are a couple examples of converter functions. In addition to the normal conversions, convert Date to datetime:

    from datetime import datetime
from js import Date
def default_converter(value, _ignored1, _ignored2):
    if isinstance(value, datetime):
        return Date.new(value.timestamp() * 1000)
    return value

    Don’t create any PyProxies, require a complete conversion or raise an error:

    def default_converter(_value, _ignored1, _ignored2):
    raise Exception("Failed to completely convert object")

    The second and third arguments are only needed for converting containers. The second argument is a conversion function which is used to convert the elements of the container with the same settings. The third argument is a “cache” function which is needed to handle self referential containers. Consider the following example. Suppose we have a Python Pair class:

    class Pair:
    def __init__(self, first, second):
        self.first = first
        self.second = second

    We can use the following default_converter to convert Pair to Array:

    from js import Array
def default_converter(value, convert, cache):
    if not isinstance(value, Pair):
        return value
    result = Array.new()
    cache(value, result);
    result.push(convert(value.first))
    result.push(convert(value.second))
    return result

    Note that we have to cache the conversion of value before converting value.first and value.second. To see why, consider a self referential pair:

    p = Pair(0, 0);
p.first = p;

    Without cache(value, result);, converting p would lead to an infinite recurse. With it, we can successfully convert p to an Array such that l[0] === l.

pyodide.ffi.unregister_js_module(name: str) → None#

Unregisters a JavaScript module with given name that has been previously registered with pyodide.registerJsModule or pyodide.ffi.register_js_module. If a JavaScript module with that name does not already exist, will raise an error. If the module has already been imported, this won’t have much effect unless you also delete the imported module from sys.modules. This is called by the JavaScript API pyodide.unregisterJsModule.

Parameters

name (str) – Name of js module

Classes:

Destroyable(*args, **kwargs)

Functions:

add_event_listener(elt, event, listener)

Wrapper for JavaScript's addEventListener() which automatically manages the lifetime of a JsProxy corresponding to the listener param.

clear_interval(interval_retval)

Wrapper for JavaScript's clearInterval() which automatically manages the lifetime of a JsProxy corresponding to the callback param.

clear_timeout(timeout_retval)

Wrapper for JavaScript's clearTimeout() which automatically manages the lifetime of a JsProxy corresponding to the callback param.

remove_event_listener(elt, event, listener)

Wrapper for JavaScript's removeEventListener() which automatically manages the lifetime of a JsProxy corresponding to the listener param.

set_interval(callback, interval)

Wrapper for JavaScript's setInterval() which automatically manages the lifetime of a JsProxy corresponding to the callback param.

set_timeout(callback, timeout)

Wrapper for JavaScript's setTimeout() which automatically manages the lifetime of a JsProxy corresponding to the callback param.
class pyodide.ffi.wrappers.Destroyable(*args, **kwargs)#
pyodide.ffi.wrappers.add_event_listener(elt: pyodide.ffi.JsDomElement, event: str, listener: collections.abc.Callable[[Any], None]) → None#

Wrapper for JavaScript’s addEventListener() which automatically manages the lifetime of a JsProxy corresponding to the listener param.

pyodide.ffi.wrappers.clear_interval(interval_retval: int | pyodide.ffi.JsProxy) → None#

Wrapper for JavaScript’s clearInterval() which automatically manages the lifetime of a JsProxy corresponding to the callback param.

pyodide.ffi.wrappers.clear_timeout(timeout_retval: int | pyodide.ffi.JsProxy) → None#

Wrapper for JavaScript’s clearTimeout() which automatically manages the lifetime of a JsProxy corresponding to the callback param.

pyodide.ffi.wrappers.remove_event_listener(elt: pyodide.ffi.JsDomElement, event: str, listener: collections.abc.Callable[[Any], None]) → None#

Wrapper for JavaScript’s removeEventListener() which automatically manages the lifetime of a JsProxy corresponding to the listener param.

pyodide.ffi.wrappers.set_interval(callback: collections.abc.Callable[[], None], interval: int) → int | pyodide.ffi.JsProxy#

Wrapper for JavaScript’s setInterval() which automatically manages the lifetime of a JsProxy corresponding to the callback param.

pyodide.ffi.wrappers.set_timeout(callback: collections.abc.Callable[[], None], timeout: int) → int | pyodide.ffi.JsProxy#

Wrapper for JavaScript’s setTimeout() which automatically manages the lifetime of a JsProxy corresponding to the callback param.