@export

You can add the @export decorator on any function to make it publicly available as an exported symbol in the compiled artifact, allowing it to be called from external code, such as Python.

# This function is internal - not callable from Python
fn internal_helper():
    print("Internal")

# This function can be called from Python as "my_exported_function"
@export
fn my_exported_function():
    print("Exported!")
    internal_helper()

# This function can be called from Python as "my_renamed_function"
@export("my_renamed_function")
fn my_other_function():
    print("Another function.")
# This function is internal - not callable from Python
fn internal_helper():
    print("Internal")

# This function can be called from Python as "my_exported_function"
@export
fn my_exported_function():
    print("Exported!")
    internal_helper()

# This function can be called from Python as "my_renamed_function"
@export("my_renamed_function")
fn my_other_function():
    print("Another function.")

The @export decorator can take two optional arguments:

An alternate name to export the function under, as shown above.
An ABI specifier. Currently only the the C ABI is supported.

Use the name and ABI specifier to export a function that complies with the C calling conventions. You must also supply a function name that is a valid C identifier. For example:

@export("my_func", ABI="C")
fn my_function(name: StaticString, ptr: UnsafePointer[NoneType]) -> None:
    pass
@export("my_func", ABI="C")
fn my_function(name: StaticString, ptr: UnsafePointer[NoneType]) -> None:
    pass