Renumbered =head tags for chapters (GH chromatic#102).

sections/advanced_oo.pod

@@ -1,4 +1,4 @@
-=head2 Advanced OO Perl
+=head1 Advanced OO Perl
 
 Z<advanced_oo>
 
@@ -8,7 +8,7 @@ abstraction also offer possibilities for obfuscation.  Only practical
 experience can help you understand the most important design techniques... but
 several principles can guide you.
 
-=head3 Favor Composition Over Inheritance
+=head2 Favor Composition Over Inheritance
 
 Novice OO designs often overuse inheritance.  It's common to see class
 hierarchies which try to model all of the behavior for entities within the
@@ -27,7 +27,7 @@ roles) improves encapsulation and reduces the possibility that any one class or
 role will grow to do too much.  Smaller, simpler, and better encapsulated
 entities are easier to understand, test, and maintain.
 
-=head3 Single Responsibility Principle
+=head2 Single Responsibility Principle
 
 When you design your object system, model the problem in terms of
 responsibilities, or reasons why each specific entity may need to change.  For
@@ -42,7 +42,7 @@ may have a C<Job>-sharing arrangement, for example.)
 When each class has a single responsibility, you can improve the encapsulation
 of class-specific data and behaviors and reduce coupling between classes.
 
-=head3 Don't Repeat Yourself
+=head2 Don't Repeat Yourself
 
 Complexity and duplication complicate development and maintenance activities.
 The DRY principle (Don't Repeat Yourself) is a reminder to seek out and to
@@ -56,7 +56,7 @@ This principle helps to reduce the possibility that important parts of your
 system can get unsynchronized, and helps you to find the optimal representation
 of the system and its data.
 
-=head3 Liskov Substitution Principle
+=head2 Liskov Substitution Principle
 
 The Liskov substitution principle suggests that subtypes of a given type
 (specializations of a class or role or subclasses of a class) should be
@@ -72,7 +72,7 @@ objects with C<PecanPie> objects in the test suite, and everything should
 passN<See Reg Braithwaite's "IS-STRICTLY-EQUIVALENT-TO-A" for more details,
 U<http://weblog.raganwald.com/2008/04/is-strictly-equivalent-to.html>.>.
 
-=head3 Subtypes and Coercions
+=head2 Subtypes and Coercions
 
 Z<subtypes>
 Z<coercions>
@@ -88,7 +88,7 @@ specify mechanisms by which to coerce data of one type to data of another type.
 
 See C<Moose::Util::TypeConstraints> and C<MooseX::Types> for more information.
 
-=head3 Immutability
+=head2 Immutability
 
 Z<immutability>
 

sections/anonymous_functions.pod

@@ -1,4 +1,4 @@
-=head2 Anonymous Functions
+=head1 Anonymous Functions
 
 Z<anonymous_functions>
 
@@ -11,7 +11,7 @@ references to it--it can do anything a named function can do.  The difference
 is that it has no name.  You always deal with anonymous functions by reference
 (see L<references> and L<function_references>).
 
-=head3 Declaring Anonymous Functions
+=head2 Declaring Anonymous Functions
 
 You may never declare an anonymous function on its own; you must construct it
 and assign it to a variable, invoke it immediately, or pass it as an argument
@@ -113,7 +113,7 @@ function parameters:
 
 =end programlisting
 
-=head3 Anonymous Function Names
+=head2 Anonymous Function Names
 
 X<anonymous functions; names>
 
@@ -204,7 +204,7 @@ Calling C<subname()> on C<$anon> and returning into C<$named> modifies that
 function, so any other reference to this function will see the same name
 C<pseudo-anonymous>.
 
-=head3 Implicit Anonymous Functions
+=head2 Implicit Anonymous Functions
 
 X<anonymous functions; implicit>
 

sections/arrays.pod

@@ -1,4 +1,4 @@
-=head2 Arrays
+=head1 Arrays
 
 Z<arrays>
 X<arrays>
@@ -17,7 +17,7 @@ The C<@> sigil denotes an array.  To declare an array:
 
 =end programlisting
 
-=head3 Array Elements
+=head2 Array Elements
 
 X<variant sigils>
 X<sigils; variance>
@@ -101,7 +101,7 @@ You can resize an array by assigning to C<$#>.  If you shrink an array, Perl
 will discard values which do not fit in the resized array.  If you expand an
 array, Perl will fill in the expanded values with C<undef>.
 
-=head3 Array Assignment
+=head2 Array Assignment
 
 You can assign to individual positions in an array directly by index:
 
@@ -174,7 +174,7 @@ version of C<my @items>.  Prefer the latter.
 
 =end sidebar
 
-=head3 Array Slices
+=head2 Array Slices
 
 X<array slice>
 X<slices; array>
@@ -232,7 +232,7 @@ used as its index:
 
 =end programlisting
 
-=head3 Array Operations
+=head2 Array Operations
 
 Managing array indices can be a hassle.  Because Perl 5 can expand or contract
 arrays as necessary, the language also provides several operations to treat
@@ -298,7 +298,7 @@ other operators are shorter and simpler to read and understand.
 Arrays often contain elements to process in a loop; see L<looping_directives>
 for more detail about Perl 5 control flow and array processing.
 
-=head3 Arrays and Context
+=head2 Arrays and Context
 
 X<list context; arrays>
 
@@ -347,7 +347,7 @@ not I<create> lists in these circumstances--they only group expressions.
 The solution to this flattening behavior is the same for passing arrays to
 functions and for creating nested arrays (L<references>).
 
-=head3 Array Interpolation
+=head2 Array Interpolation
 
 X<array interpolation>
 X<interpolation; arrays>

sections/attributes.pod

@@ -1,4 +1,4 @@
-=head2 Attributes
+=head1 Attributes
 
 Z<attributes>
 
@@ -15,7 +15,7 @@ they I<can> offer compelling benefits of maintenance and clarity.
 
 =end sidebar
 
-=head3 Using Attributes
+=head2 Using Attributes
 
 In its simplest form, an attribute is a colon-preceded identifier attached to a
 variable or function declaration:
@@ -68,7 +68,7 @@ The Catalyst web framework also uses attributes to determine the visibility and
 
 =end sidebar
 
-=head3 Drawbacks of Attributes
+=head2 Drawbacks of Attributes
 
 X<pragmas; attributes>
 X<attributes.pm>

sections/autoload.pod

@@ -1,4 +1,4 @@
-=head2 AUTOLOAD
+=head1 AUTOLOAD
 
 Z<autoload>
 
@@ -39,7 +39,7 @@ C<AUTOLOAD()> to emit a message to demonstrate this:
 
 =end programlisting
 
-=head3 Basic Features of AUTOLOAD
+=head2 Basic Features of AUTOLOAD
 
 The C<AUTOLOAD()> function receives the arguments passed to the undefined
 function in C<@_> directly.  You may manipulate these arguments as you like:
@@ -104,7 +104,7 @@ Finally, whatever C<AUTOLOAD()> returns, the original call receives:
 So far, these examples have merely intercepted calls to undefined functions.
 You have other options.
 
-=head3 Redispatching Methods in AUTOLOAD()
+=head2 Redispatching Methods in AUTOLOAD()
 
 X<AUTOLOAD; redispatch>
 X<AUTOLOAD; delegation>
@@ -143,7 +143,7 @@ it dereferences the proxied object from a blessed scalar reference, extracts
 the name of the undefined method, then invokes the method of that name on the
 proxied object, passing the given arguments.
 
-=head3 Generating Code in AUTOLOAD()
+=head2 Generating Code in AUTOLOAD()
 
 X<AUTOLOAD; code installation>
 
@@ -215,7 +215,7 @@ This has the same effect as invoking C<$method> directly, except that
 C<AUTOLOAD()> will no longer appear in the list of calls available from
 C<caller()>, so it looks like the generated method was simply called directly.
 
-=head3 Drawbacks of AUTOLOAD
+=head2 Drawbacks of AUTOLOAD
 
 Z<autoload_drawbacks>
 

sections/barewords.pod

@@ -1,4 +1,4 @@
-=head2 Barewords
+=head1 Barewords
 
 Z<barewords>
 
@@ -23,7 +23,7 @@ for good reason.
 
 Even so, barewords are permissible in several places in Perl 5 for good reason.
 
-=head3 Good Uses of Barewords
+=head2 Good Uses of Barewords
 
 X<barewords; pros>
 X<hashes; bareword keys>
@@ -118,7 +118,7 @@ bareword; Perl 5 knows everything it needs to know to parse all occurrences of
 that function appropriately.  Note that all of the drawbacks of prototypes
 still apply.
 
-=head3 Ill-Advised Uses of Barewords
+=head2 Ill-Advised Uses of Barewords
 
 X<barewords; cons>
 

sections/blessed_references.pod

@@ -1,4 +1,4 @@
-=head2 Blessed References
+=head1 Blessed References
 
 Z<blessed_references>
 
@@ -149,7 +149,7 @@ thing with regard to encapsulation as well as genericity.
 
 =end sidebar
 
-=head3 Method Lookup and Inheritance
+=head2 Method Lookup and Inheritance
 
 X<method dispatch>
 X<objects; methods>
@@ -255,7 +255,7 @@ behavior with method dispatch.  Enable it in your class with:
 Unless you're writing a complex framework with multiple interoperable plugins,
 you likely never need to use this.
 
-=head3 AUTOLOAD
+=head2 AUTOLOAD
 
 X<AUTOLOAD>
 X<objects; AUTOLOAD>
@@ -270,7 +270,7 @@ for more details.
 As you might expect, this can get quite complex in the face of multiple
 inheritance and multiple potential C<AUTOLOAD> targets.
 
-=head3 Method Overriding and SUPER
+=head2 Method Overriding and SUPER
 
 You may override methods in the default Perl 5 OO system as well as in Moose.
 Unfortunately, core Perl 5 provides no mechanism for indicating your I<intent>
@@ -310,7 +310,7 @@ can work around this for you.  Moose handles it nicely as well.
 
 =end sidebar
 
-=head3 Strategies for Coping with Blessed References
+=head2 Strategies for Coping with Blessed References
 
 Avoid C<AUTOLOAD> where possible.  If you I<must> use it, use forward
 declarations of your functions (L<functions>) to help Perl know which

sections/builtins.pod

@@ -1,4 +1,4 @@
-=head1 Builtins
+=head0 Builtins
 
 Z<style>
 

sections/chapter_00.pod

@@ -19,7 +19,7 @@ full understanding of Perl.
 
 You can learn this too.
 
-=head1 Running Modern Perl
+=head0 Running Modern Perl
 
 You don't have to install a new version of Perl to take advantage of most of
 this book, but the examples given assume that you're using Perl 5.10 or newer.

sections/chapter_01.pod

@@ -1,4 +1,4 @@
-=head1 The Perl Philosophy
+=head0 The Perl Philosophy
 
 Perl is a language for getting things done.  It's flexible, forgiving, and
 malleable.  In the hands of a capable programmer, it can perform almost any

sections/chapter_02.pod

@@ -1,4 +1,4 @@
-=head1 Perl and Its Community
+=head0 Perl and Its Community
 
 One of Larry's main goals for Perl 5 was to encourage Perl development and
 evolution outside the core distribution.  Perl 4 had several forks, because

sections/chapter_03.pod

@@ -1,4 +1,4 @@
-=head1 The Perl Language
+=head0 The Perl Language
 
 The Perl language has several smaller parts which combine to form its syntax.
 Unlike spoken language, where nuance and tone of voice and intuition allow

sections/chapter_04.pod

@@ -1,4 +1,4 @@
-=head1 Operators
+=head0 Operators
 
 Z<operators>
 X<operators>

sections/chapter_05.pod

@@ -1,4 +1,4 @@
-=head1 Functions
+=head0 Functions
 
 X<function>
 X<subroutine>

sections/chapter_06.pod

@@ -1,4 +1,4 @@
-=head1 Regular Expressions and Matching
+=head0 Regular Expressions and Matching
 
 Z<regular_expressions>
 

sections/chapter_07.pod

@@ -1,4 +1,4 @@
-=head1 Objects
+=head0 Objects
 
 Writing large programs requires more discipline than writing small programs,
 due to the difficulty of managing all of the details of your program

sections/chapter_08.pod

@@ -1,4 +1,4 @@
-=head1 Stylish Perl
+=head0 Stylish Perl
 
 Programming and programming I<well> are related, but distinct skills.  If we
 only wrote programs once and never had to modify or maintain them, if our

sections/chapter_09.pod

@@ -1,4 +1,4 @@
-=head1 Writing Real Programs
+=head0 Writing Real Programs
 
 Z<writing_real_programs>
 

sections/chapter_10.pod

@@ -1,4 +1,4 @@
-=head1 Perl Beyond Syntax
+=head0 Perl Beyond Syntax
 
 Perl 5 is a large language, like any language intended to solve problems in the
 real world.  Effective Perl programs require more than mere understanding of

sections/chapter_11.pod

@@ -1,4 +1,4 @@
-=head1 What to Avoid
+=head0 What to Avoid
 
 Perl 5 isn't perfect.  Some features seemed like good ideas at the time, but
 they're difficult to use correctly.  Others don't work as anyone might expect.

sections/chapter_12.pod

@@ -1,4 +1,4 @@
-=head1 What's Missing
+=head0 What's Missing
 
 Perl 5 isn't perfect, at least as it behaves by default.  Some options are
 available in the core.  More are available from the CPAN.  Experienced Perl