A module that walks the Perl syntax tree,
printing concise info about the internal OPs of a Perl
program's syntax tree. The format of the information
displayed is customizable. Its function is similar to that of
Perl's -Dx debugging flag or
the B::Terse module, but it is more sophisticated and flexible.
perl -MO=Concise[,options] program
program is the name of the Perl script to
compile. Any non-option arguments are treated as the names of objects
to be saved; the main program is assumed if there are no extra
arguments. Possible options are:
Prints OPs in the order they appear in the OP tree (a preorder
traversal, starting at the root). Default.
Prints OPs in the order they would normally execute. For the majority
of constructs, this is a postorder traversal of the tree, ending at
Prints OPs in a text approximation of a tree, with the root of the
tree at the left and
"left-to-right" order of children
transformed into "top-to-bottom".
Unsuitable for large programs.
Uses a tree format in which the minimum amount of space is used for
the lines connecting nodes (one character in most cases).
Uses a tree format that uses longer edges to separate OP nodes.
Uses tree-connecting characters drawn from the VT100 line-drawing set.
Draws the tree with standard ASCII characters such as
+ and |. Default.
Includes the main program in the output, even if subroutines were
Prints OP sequence numbers in base n, with n <= 62. The default is
Prints sequence numbers with the most significant digit first.
Prints sequence numbers with the least significant digit first.
Uses the author's favorite set of formatting
Uses formatting conventions that emulate the output of B::Terse.
Uses formatting conventions in which the name of each OP, rather than
written out in full, is represented by a one- or two-character
Uses formatting conventions reminiscient of B::Debug.
Uses formatting conventions read from the environment variables
B_CONCISE_FORMAT, B_CONCISE_GOTO_FORMAT, and B_CONCISE_TREE_FORMAT.
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