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NAME

Devel::MAT::Graph - a set of references between related SVs

DESCRIPTION

Instances of this class represent an entire graph of references between related SVs, as a helper method for return values from various Devel::MAT methods, which might be used for some sort of screen layout or other analysis tasks.

CONSTRUCTOR

new

   $graph = Devel::MAT::Graph->new( $dumpfile )

Constructs a new Devel::MAT::Graph instance backed by the given dumpfile (which is only actually used to make the $node->sv method work).

MUTATION METHODS

add_sv

   $graph->add_sv( $sv )

Makes the graph aware of the given Devel::MAT::SV. This is not strictly necessary before calling add_ref or add_root, but ensures that has_sv will return true immediately after it, and so can be used as a sentinel for recursion control.

add_ref

   $graph->add_ref( $from_sv, $to_sv, $desc )

Adds an edge to the graph, from and to the given SVs, with the given description.

add_root

   $graph->add_root( $from_sv, $desc )

Adds a root edge to the graph, at the given SV with the given description.

QUERY METHODS

has_sv

   $bool = $graph->has_sv( $sv )

Returns true if the graph has edges or roots for the given SV, or it has at least been given to add_sv.

get_sv_node

   $node = $graph->get_sv_node( $sv )

Returns a Node object for the given SV.

get_root_nodes

   @desc_nodes = $graph->get_root_nodes

Returns an even-sized list of pairs, containing root descriptions and the nodes having those roots, in no particular order.

NODE OBJECTS

The values returned by get_sv_node respond to the following methods:

graph

   $graph = $node->graph

Returns the containing Devel::MAT::Graph instance.

addr

   $addr = $node->addr

Returns the address of the SV represented by this node.

sv

   $sv = $node->sv

Returns the SV object itself, as taken from the dumpfile instance.

roots

   @roots = $node->roots

Returns any root descriptions given (by calls to $graph->add_root for the SV at this node.

   $graph->add_root( $sv, $desc );

   ( $desc, ... ) = $graph->get_sv_node( $sv )->roots

edges_out

   @edges = $node->edges_out

Returns an even-sized list of any edge descriptions and more Node objects given as references (by calls to $graph->add_ref) from the SV at this node.

   $graph->add_ref( $from_sv, $to_sv, $desc )

   ( $desc, $to_edge, ... ) = $graph->get_sv_node( $from_sv )->edges_out

edges_out (scalar)

   $n_edges = $node->edges_out

In scalar context, returns the number of edges that exist; i.e. half the size of the pairlist that would be returned in list context.

edges_in

   @edges = $node->edges_in

Similar to edges_out, but returns edges in the opposite direction; i.e. edges of references to this node.

   $graph->add_ref( $from_sv, $to_sv, $desc )

   ( $desc, $from_edge, ... ) = $graph->get_sv_node( $to_sv )->edges_in

edges_in (scalar)

   $n_edges = $node->edges_out

In scalar context, returns the number of edges that exist; i.e. half the size of the pairlist that would be returned in list context.

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>