Supposedly, Attribute::Handlers can act at any compilation stage, though the default is CHECK, as that's a point at which most things are compiled and in place. The big limitation is that the name in the symbol table for a subroutine isn't set at the time attributes are first processed -- only the package name and the code reference (that later gets stored in the symbol table) are available.

Technically, the MODIFY_*_ATTRIBUTES from Attribute::Handlers runs immediately during compilation (like a BEGIN block) -- but by default, Attribute::Handlers just stores everything it can about the call at that point. Later, during CHECK, it calls the appropriate handlers on the previously stored information, which, among other things, allows looking up the name of the coderef in the symbol table to find the name of a subroutine.

-xdg

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In reply to Re^2: How do you use/create subroutine attributes? by xdg
in thread How do you use/create subroutine attributes? by mshiltonj

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