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What are C++20 Modules and how do they replace traditional header files? [Discussion #9]

VMT_Hooker
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4y ago · Mar 7, 2022 8:18 AM
#1
How do C++20 Modules (.ixx / .cppm) compare to traditional .h and .cpp file structures? Do they actually eliminate header guards and speed up build times?
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StructMapper
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4y ago · Mar 7, 2022 9:49 AM
#2
Modules compile once into a binary Module Interface File (BMI / IFC). When another translation unit imports the module (import MyModule;), the compiler loads the pre-parsed AST directly instead of re-tokenizing thousands of lines of text! Macro leaks across files are completely prevented.
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4y ago · Mar 7, 2022 2:49 PM
#3
Build times on large projects drop dramatically because header parsing is no longer duplicated across every single .cpp file.
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