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What are C++20 Modules and how do they replace traditional header files? [Discussion #3]

GarbageCollector
CLR Internals
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3y ago · Sep 7, 2022 12:24 PM
#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?
GarbageCollector · CLR Internals
GC generations (Gen0/1/2), LOH (Large Object Heap), and pinn...
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PInvokeMaster
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3y ago · Sep 7, 2022 3:38 PM
#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.
PInvokeMaster · Interoperability Specialist
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EventDriven
Reactive Extensions
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3y ago · Sep 7, 2022 5:38 PM
#3
Build times on large projects drop dramatically because header parsing is no longer duplicated across every single .cpp file.
EventDriven · Reactive Extensions
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