micropython/tests/cpydiff/types_int_subclassconv.py

"""
categories: Types,int
description: No int conversion for int-derived types available
cause: Unknown
workaround: Avoid subclassing builtin types unless really needed. Prefer https://en.wikipedia.org/wiki/Composition_over_inheritance .
"""
class A(int):
    __add__ = lambda self, other: A(int(self) + other)

a = A(42)
print(a+a)
tests/cpydiff: Add initial set of tests for uPy-CPython differences. These tests are intended to fail, as they provide a programatic record of differences between uPy and CPython. They also contain a special comment at the start of the file which has meta-data describing the difference, including known causes and known workarounds. 2017-02-07 04:55:37 +00:00			`"""`
			`categories: Types,int`
			`description: No int conversion for int-derived types available`
			`cause: Unknown`
tests/cpydiff/: Improve wording, add more workarounds. 2017-07-09 11:33:55 +00:00			`workaround: Avoid subclassing builtin types unless really needed. Prefer https://en.wikipedia.org/wiki/Composition_over_inheritance .`
tests/cpydiff: Add initial set of tests for uPy-CPython differences. These tests are intended to fail, as they provide a programatic record of differences between uPy and CPython. They also contain a special comment at the start of the file which has meta-data describing the difference, including known causes and known workarounds. 2017-02-07 04:55:37 +00:00			`"""`
			`class A(int):`
			`__add__ = lambda self, other: A(int(self) + other)`

			`a = A(42)`
			`print(a+a)`