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Dependency Inversion Principle

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Dominic Yeboah
·

1 min read

Dependency Inversion Principle: High-level modules should not depend on low-level modules. Both should depend on abstractions. Here is an example of a high-level module that violates the Dependency Inversion Principle by depending on a low-level module:

import lowlevel_module

class HighLevelModule:
    def do_something(self):
        lowlevel_module.do_something_lowlevel()

To adhere to the Dependency Inversion Principle, we can introduce an abstraction between the high-level and low-level modules:

class LowLevelModule:
    def do_something_lowlevel(self):
        pass

class HighLevelModule:
    def __init__(self, lowlevel_module):
        self.lowlevel_module = lowlevel_module

    def do_something(self):
        self.lowlevel_module.do_something_lowlevel()

lowlevel_module = LowLevelModule()
highlevel_module = HighLevelModule(lowlevel_module)
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