This module provides syntax highlighting for Perl code. The design bias is
roughly line-oriented and streamed (ie, processing a file line-by-line in a
single pass). Provisions _may_ be made in the future for tasks related to
"back-tracking" (ie, re-doing a single line in the middle of a stream) such
as speeding up state copying.

Constructors
The only constructor provided is 'new()'. When called on an existing
object, 'new()' will create a new _*copy*_ of that object. Otherwise,
'new()' creates a new copy of the (internal) _Default Object_. Note
that the use of the procedural syntax modifies the _Default Object_ and
that those changes _will_ be reflected in any subsequent 'new()' calls.

Formatting
Formatting is done using the 'format_string()' method. Call
'format_string()' with one or more strings to format, or it will
default to using '$_'.