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8.20 B::Xref

Perl compiler backend that generates a cross-reference listing of variables, subroutines, and formats in a Perl program. Results are grouped by file, then subroutine, then package, then objects within the package with line numbers. The line numbers are given as a comma-separated list. A line number may be preceded by one of the following code letters:

Code Meaning
% Subroutine or method call
f Format definition
i Introduction, e.g., a lexical defined with my
s Subroutine definition

Invoke B::Xref like this:

perl -MO=Xref[,
program is the Perl program whose cross-reference you want. Options are separated by commas and follow normal backend option conventions. The possible options are:


Specifies internal debug options. Most useful if specified with -r option. Debug options are:


Prints each operator as it's being processed, in the execution order of the program.


Prints the object on the top of the stack as it is being tracked.


Sends output to filename instead of STDOUT.


Produces raw output in machine-readable form for each definition or use of a variable, subroutine, or format.