16 Library introduction [library]

16.3 Definitions [definitions]

16.3.23[defns.replacement]replacement function

non-reserved function whose definition is provided by a C++ program
[Note
:
Only one definition for such a function is in effect for the duration of the program's execution, as the result of creating the program ([lex.phases]) and resolving the definitions of all translation units ([basic.link]).
end note
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