Perl Best Practices

by Conway, Damian

• ISBN13: 9780596001735
• ISBN10: 0596001738
• Format: Paperback
• Copyright: 2005-08-01
• Publisher: Oreilly & Associates Inc

Summary

The first book on Perl modules written by a well-known and well-respected member of the Perl community. Includes case studies from the author's vast repertoire of working modules. Coverage of testing and CPAN module specifications are included along with material on distribution files and other coding considerations for intermediate to advanced Perl programmers.

Author Biography

Damian Conway holds a PhD in Computer Science and is an honorary Associate Professor with the School of Computer Science and Software Engineering at Monash University, Melbourne, Australia.

Currently he runs an international IT training company--Thoughtstream--which provides programmer development from beginner to masterclass level throughout Europe, North America, and Australasia.

Damian was the winner of the 1998, 1999, and 2000 Larry Wall Awards for Practical Utility. The best technical paper at the annual Perl Conference was subsequently named in his honour. He is a member of the technical committee for The Perl Conference, a keynote speaker at many Open Source conferences, a former columnist for The Perl Journal, and author of the book Object Oriented Perl. In 2001 Damian received the first "Perl Foundation Development Grant" and spent 20 months working on projects for the betterment of Perl.

A popular speaker and trainer, he is also the author of numerous well-known Perl modules, including Parse::RecDescent (a sophisticated parsing tool), Class::Contract (design-by-contract programming in Perl), Lingua::EN::Inflect (rule-based English transformations for text generation), Class::Multimethods (multiple dispatch polymorphism), Text::Autoformat (intelligent automatic reformatting of plaintext), Switch (Perl's missing case statement), NEXT (resumptive method dispatch), Filter::Simple (Perl-based source code manipulation), Quantum::Superpositions (auto-parallelization of serial code using a quantum mechanical metaphor), and Lingua::Romana::Perligata (programming in Latin).

Most of his time is now spent working with Larry Wall on the design of the new Perl 6 programming language.

Table of Contents

Preface	xv
Best Practices	1	(7)
Three Goals	3	(2)
This Book	5	(2)
Rehabiting	7	(1)
Code Layout	8	(28)
Bracketing	9	(2)
Keywords	11	(1)
Subroutines and Variables	12	(1)
Builtins	13	(1)
Keys and Indices	14	(1)
Operators	14	(1)
Semicolons	15	(2)
Commas	17	(1)
Line Lengths	18	(1)
Indentation	19	(1)
Tabs	20	(2)
Blocks	22	(1)
Chunking	23	(1)
Elses	24	(2)
Vertical Alignment	26	(1)
Breaking Long Lines	27	(2)
Non-Terminal Expressions	29	(1)
Breaking by Precedence	29	(1)
Assignments	30	(1)
Ternaries	31	(1)
Lists	32	(1)
Automated Layout	33	(3)
Naming Conventions	36	(15)
Identifiers	37	(3)
Booleans	40	(1)
Reference Variables	41	(2)
Arrays and Hashes	43	(1)
Underscores	44	(1)
Capitalization	45	(1)
Abbreviations	46	(1)
Ambiguous Abbreviations	47	(1)
Ambiguous Names	48	(1)
Utility Subroutines	49	(2)
Values and Expressions	51	(22)
String Delimiters	51	(2)
Empty Strings	53	(1)
Single-Character Strings	53	(1)
Escaped Characters	54	(1)
Constants	55	(3)
Leading Zeros	58	(1)
Long Numbers	59	(1)
Multiline Strings	60	(1)
Here Documents	61	(1)
Heredoc Indentation	61	(1)
Heredoc Terminators	62	(2)
Heredoc Quoters	64	(1)
Barewords	65	(1)
Fat Commas	66	(2)
Thin Commas	68	(2)
Low-Precedence Operators	70	(1)
Lists	71	(1)
List Membership	71	(2)
Variables	73	(20)
Lexical Variables	73	(2)
Package Variables	75	(2)
Localization	77	(1)
Initialization	78	(1)
Punctuation Variables	79	(2)
Localizing Punctuation Variables	81	(1)
Match Variables	82	(3)
Dollar-Underscore	85	(3)
Array Indices	88	(1)
Slicing	89	(1)
Slice Layout	90	(1)
Slice Factoring	90	(3)
Control Structures	93	(39)
If Blocks	93	(1)
Postfix Selectors	94	(2)
Other Postfix Modifiers	96	(1)
Negative Control Statements	97	(3)
C-Style Loops	100	(1)
Unnecessary Subscripting	101	(2)
Necessary Subscripting	103	(2)
Iterator Variables	105	(3)
Non-Lexical Loop Iterators	108	(2)
List Generation	110	(1)
List Selections	111	(1)
List Transformation	112	(1)
Complex Mappings	113	(1)
List Processing Side Effects	114	(3)
Multipart Selections	117	(1)
Value Switches	118	(3)
Tabular Ternaries	121	(2)
do-while Loops	123	(2)
Linear Coding	125	(1)
Distributed Control	126	(2)
Redoing	128	(1)
Loop Labels	129	(3)
Documentation	132	(17)
Types of Documentation	132	(1)
Boilerplates	133	(5)
Extended Boilerplates	138	(1)
Location	139	(1)
Contiguity	140	(1)
Position	140	(1)
Technical Documentation	141	(1)
Comments	141	(1)
Algorithmic Documentation	142	(1)
Elucidating Documentation	143	(1)
Defensive Documentation	144	(1)
Indicative Documentation	145	(1)
Discursive Documentation	145	(3)
Proofreading	148	(1)
Built-in Functions	149	(26)
Sorting	149	(3)
Reversing Lists	152	(1)
Reversing Scalars	153	(1)
Fixed-Width Data	154	(3)
Separated Data	157	(1)
Variable-Width Data	158	(3)
String Evaluations	161	(3)
Automating Sorts	164	(1)
Substrings	165	(1)
Hash Values	166	(1)
Globbing	167	(1)
Sleeping	168	(1)
Mapping and Grepping	169	(1)
Utilities	170	(5)
Subroutines	175	(27)
Call Syntax	175	(2)
Homonyms	177	(1)
Argument Lists	178	(4)
Named Arguments	182	(2)
Missing Arguments	184	(1)
Default Argument Values	185	(1)
Scalar Return Values	186	(2)
Contextual Return Values	188	(3)
Multi-Contextual Return Values	191	(3)
Prototypes	194	(3)
Implicit Returns	197	(2)
Returning Failure	199	(3)
I/O	202	(25)
Filehandles	202	(2)
Indirect Filehandles	204	(1)
Localizing Filehandles	205	(2)
Opening Cleanly	207	(1)
Error Checking	208	(1)
Cleanup	209	(2)
Input Loops	211	(1)
Line-Based Input	212	(1)
Simple Slurping	213	(1)
Power Slurping	214	(2)
Standard Input	216	(1)
Printing to Filehandles	217	(1)
Simple Prompting	217	(1)
Interactivity	218	(2)
Power Prompting	220	(2)
Progress Indicators	222	(2)
Automatic Progress Indicators	224	(1)
Autoflushing	224	(3)
References	227	(8)
Dereferencing	227	(1)
Braced References	228	(2)
Symbolic References	230	(2)
Cyclic References	232	(3)
Regular Expressions	235	(38)
Extended Formatting	236	(1)
Line Boundaries	237	(2)
String Boundaries	239	(1)
End of String	240	(1)
Matching Anything	240	(2)
Lazy Flags	242	(1)
Brace Delimiters	242	(4)
Other Delimiters	246	(1)
Metacharacters	247	(1)
Named Characters	247	(1)
Properties	248	(1)
Whitespace	249	(1)
Unconstrained Repetitions	250	(2)
Capturing Parentheses	252	(1)
Captured Values	253	(1)
Capture Variables	254	(3)
Piecewise Matching	257	(2)
Tabular Regexes	259	(2)
Constructing Regexes	261	(2)
Canned Regexes	263	(2)
Alternations	265	(1)
Factoring Alternations	266	(3)
Backtracking	269	(2)
String Comparisons	271	(2)
Error Handling	273	(26)
Exceptions	274	(4)
Builtin Failures	278	(1)
Contextual Failure	279	(1)
Systemic Failure	280	(1)
Recoverable Failure	281	(2)
Reporting Failure	283	(1)
Error Messages	284	(2)
Documenting Errors	286	(1)
OO Exceptions	287	(3)
Volatile Error Messages	290	(1)
Exception Hierarchies	291	(1)
Processing Exceptions	292	(1)
Exception Classes	293	(3)
Unpacking Exceptions	296	(3)
Command-Line Processing	299	(19)
Command-Line Structure	300	(1)
Command-Line Conventions	301	(2)
Meta-options	303	(1)
In-situ Arguments	304	(2)
Command-Line Processing	306	(5)
Interface Consistency	311	(3)
Interapplication Consistency	314	(4)
Objects	318	(41)
Using OO	319	(1)
Criteria	320	(2)
Pseudohashes	322	(1)
Restricted Hashes	322	(1)
Encapsulation	323	(10)
Constructors	333	(1)
Cloning	334	(2)
Destructors	336	(2)
Methods	338	(2)
Accessors	340	(6)
Lvalue Accessors	346	(3)
Indirect Objects	349	(2)
Class Interfaces	351	(3)
Operator Overloading	354	(2)
Coercions	356	(3)
Class Hierarchies	359	(38)
Inheritance	360	(1)
Objects	361	(4)
Blessing Objects	365	(2)
Constructor Arguments	367	(4)
Base Class Initialization	371	(5)
Construction and Destruction	376	(7)
Automating Class Hierarchies	383	(1)
Attribute Demolition	384	(3)
Attribute Building	387	(1)
Coercions	388	(1)
Cumulative Methods	389	(4)
Autoloading	393	(4)
Modules	397	(23)
Interfaces	397	(4)
Refactoring	401	(3)
Version Numbers	404	(1)
Version Requirements	405	(2)
Exporting	407	(2)
Declarative Exporting	409	(2)
Interface Variables	411	(4)
Creating Modules	415	(2)
The Standard Library	417	(1)
CPAN	418	(2)
Testing and Debugging	420	(21)
Test Cases	420	(1)
Modular Testing	421	(3)
Test Suites	424	(1)
Failure	425	(1)
What to Test	426	(1)
Debugging and Testing	427	(2)
Strictures	429	(2)
Warnings	431	(1)
Correctness	432	(1)
Overriding Strictures	433	(3)
The Debugger	436	(1)
Manual Debugging	437	(2)
Semi-Automatic Debugging	439	(2)
Miscellanea	441	(28)
Revision Control	441	(1)
Other Languages	442	(3)
Configuration Files	445	(4)
Formats	449	(2)
Ties	451	(2)
Cleverness	453	(1)
Encapsulated Cleverness	454	(2)
Benchmarking	456	(3)
Memory	459	(1)
Caching	460	(2)
Memoization	462	(1)
Caching for Optimization	463	(1)
Profiling	464	(2)
Enbugging	466	(3)
A. Essential Perl Best Practices	469	(3)
B. Perl Best Practices	472	(10)
C. Editor Configurations	482	(5)
D. Recommended Modules and Utilities	487	(6)
E. Bibliography	493	(2)
Index	495