| 1 | =head1 NAME
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| 2 |
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| 3 | perlmodstyle - Perl module style guide
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| 4 |
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| 5 | =head1 INTRODUCTION
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| 6 |
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| 7 | This document attempts to describe the Perl Community's "best practice"
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| 8 | for writing Perl modules. It extends the recommendations found in
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| 9 | L<perlstyle> , which should be considered required reading
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| 10 | before reading this document.
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| 11 |
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| 12 | While this document is intended to be useful to all module authors, it is
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| 13 | particularly aimed at authors who wish to publish their modules on CPAN.
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| 14 |
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| 15 | The focus is on elements of style which are visible to the users of a
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| 16 | module, rather than those parts which are only seen by the module's
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| 17 | developers. However, many of the guidelines presented in this document
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| 18 | can be extrapolated and applied successfully to a module's internals.
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| 19 |
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| 20 | This document differs from L<perlnewmod> in that it is a style guide
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| 21 | rather than a tutorial on creating CPAN modules. It provides a
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| 22 | checklist against which modules can be compared to determine whether
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| 23 | they conform to best practice, without necessarily describing in detail
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| 24 | how to achieve this.
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| 25 |
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| 26 | All the advice contained in this document has been gleaned from
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| 27 | extensive conversations with experienced CPAN authors and users. Every
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| 28 | piece of advice given here is the result of previous mistakes. This
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| 29 | information is here to help you avoid the same mistakes and the extra
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| 30 | work that would inevitably be required to fix them.
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| 31 |
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| 32 | The first section of this document provides an itemized checklist;
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| 33 | subsequent sections provide a more detailed discussion of the items on
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| 34 | the list. The final section, "Common Pitfalls", describes some of the
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| 35 | most popular mistakes made by CPAN authors.
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| 36 |
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| 37 | =head1 QUICK CHECKLIST
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| 38 |
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| 39 | For more detail on each item in this checklist, see below.
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| 40 |
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| 41 | =head2 Before you start
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| 42 |
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| 43 | =over 4
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| 44 |
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| 45 | =item *
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| 46 |
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| 47 | Don't re-invent the wheel
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| 48 |
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| 49 | =item *
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| 50 |
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| 51 | Patch, extend or subclass an existing module where possible
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| 52 |
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| 53 | =item *
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| 54 |
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| 55 | Do one thing and do it well
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| 56 |
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| 57 | =item *
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| 58 |
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| 59 | Choose an appropriate name
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| 60 |
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| 61 | =back
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| 62 |
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| 63 | =head2 The API
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| 64 |
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| 65 | =over 4
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| 66 |
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| 67 | =item *
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| 68 |
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| 69 | API should be understandable by the average programmer
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| 70 |
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| 71 | =item *
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| 72 |
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| 73 | Simple methods for simple tasks
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| 74 |
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| 75 | =item *
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| 76 |
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| 77 | Separate functionality from output
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| 78 |
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| 79 | =item *
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| 80 |
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| 81 | Consistent naming of subroutines or methods
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| 82 |
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| 83 | =item *
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| 84 |
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| 85 | Use named parameters (a hash or hashref) when there are more than two
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| 86 | parameters
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| 87 |
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| 88 | =back
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| 89 |
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| 90 | =head2 Stability
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| 91 |
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| 92 | =over 4
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| 93 |
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| 94 | =item *
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| 95 |
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| 96 | Ensure your module works under C<use strict> and C<-w>
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| 97 |
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| 98 | =item *
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| 99 |
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| 100 | Stable modules should maintain backwards compatibility
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| 101 |
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| 102 | =back
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| 103 |
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| 104 | =head2 Documentation
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| 105 |
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| 106 | =over 4
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| 107 |
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| 108 | =item *
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| 109 |
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| 110 | Write documentation in POD
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| 111 |
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| 112 | =item *
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| 113 |
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