MicroPython类库

本章介绍了构成micropython的模块（函数和类库）。有几类模块:

  • 内置模块：标准Python功能的子集，用户不能扩展。
  • 扩展模块：实现了Python功能的一个子集，并提供用户扩展（通过Python代码）。
  • 扩展模块：实现micropython的Python标准库。
  • 硬件驱动模块:特定端口或者硬件驱动的模块，因此不可移植。

Note about the availability of modules and their contents: This documentation in general aspires to describe all modules and functions/classes which are implemented in MicroPython. However, MicroPython is highly configurable, and each port to a particular board/embedded system makes available only a subset of MicroPython libraries. For officially supported ports, there is an effort to either filter out non-applicable items, or mark individual descriptions with "Availability:" clauses describing which ports provide a given feature. With that in mind, please still be warned that some functions/classes in a module (or even the entire module) described in this documentation may be unavailable in a particular build of MicroPython on a particular board. The best place to find general information of the availability/non-availability of a particular feature is the "General Information" section which contains information pertaining to a specific port.

Beyond the built-in libraries described in this documentation, many more modules from the Python standard library, as well as further MicroPython extensions to it, can be found in the micropython-lib repository.

Python标准库和微型库

标准的Python库被 “微型化”后，就是micropython标准库。它们仅仅提供了该模块的核心功能。一些模块没有直接使用标准的Python的名字，而是冠以"u"，例如``ujson``代替``json``。也就是说micropython标准库（=微型库），只实现了一部分模块功能。通过他们的名字不同，用户有选择的去写一个Python级模块扩展功能，也是为实现更好的兼容性。

在嵌入式平台上，可添加Python级别封装库从而实现命名兼容CPython，微模块即可调用他们的u-name，也可以调用non-u-name。根据non-u-name包路径的文件可重写。

例如，``import json``的话，首先搜索一个``json.py``文件或``json``目录进行加载。如果没有找到，它回退到加载内置``ujson``模块。