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Devel::MAT::Tool::Reachability - analyse how SVs are reachable


This Devel::MAT tool determines which SVs are reachable via any known roots and which are not. For reachable SVs, they are classified into several broad categories:

  • SVs that directly make up the symbol table.

  • SVs that form the padlist of functions or store the names of lexical variables.

  • SVs that hold the value of lexical variables.

  • User data stored in package globals, lexical variables, or referenced recursively via structures stored in them.

  • Miscellaneous other SVs that are used to implement the internals of the interpreter.


This tool adds the following SV methods.


   $r = $sv->reachable;

Returns true if the SV is reachable from a known root.


Paul Evans <>