README
1NAME
2 Perl::MinimumVersion - Find a minimum required version of perl for Perl
3 code
4
5SYNOPSIS
6 # Create the version checking object
7 $object = Perl::MinimumVersion->new( $filename );
8 $object = Perl::MinimumVersion->new( \$source );
9 $object = Perl::MinimumVersion->new( $ppi_document );
10
11 # Find the minimum version
12 $version = $object->minimum_version;
13
14DESCRIPTION
15 "Perl::MinimumVersion" takes Perl source code and calculates the minimum
16 version of perl required to be able to run it. Because it is based on
17 PPI, it can do this without having to actually load the code.
18
19 Currently it tests both the syntax of your code, and the use of explicit
20 version dependencies such as "require 5.005".
21
22 Future plans are to also add support for tracing module dependencies.
23
24 Using "Perl::MinimumVersion" is dead simple, the synopsis pretty much
25 covers it.
26
27 The distribution comes with a script called perlver, which is the
28 easiest way to run "Perl::MinimumVersion" on your code:
29
30 % perlver lib/Foo/Bar.pm
31
32 See the documentation for perlver for more details.
33
34METHODS
35 new
36 # Create the version checking object
37 $object = Perl::MinimumVersion->new( $filename );
38 $object = Perl::MinimumVersion->new( \$source );
39 $object = Perl::MinimumVersion->new( $ppi_document );
40
41 The "new" constructor creates a new version checking object for a
42 PPI::Document. You can also provide the document to be read as a file
43 name, or as a "SCALAR" reference containing the code.
44
45 Returns a new "Perl::MinimumVersion" object, or "undef" on error.
46
47 Document
48 The "Document" accessor can be used to get the PPI::Document object back
49 out of the version checker.
50
51 minimum_version
52 The "minimum_version" method is the primary method for finding the
53 minimum perl version required based on "all" factors in the document.
54
55 At the present time, this is just syntax and explicit version checks, as
56 Perl::Depends is not yet completed.
57
58 Returns a version object, or "undef" on error.
59
60 minimum_explicit_version
61 The "minimum_explicit_version" method checks through Perl code for the
62 use of explicit version dependencies such as.
63
64 use 5.006;
65 require 5.005_03;
66
67 Although there is almost always only one of these in a file, if more
68 than one are found, the highest version dependency will be returned.
69
70 Returns a version object, false if no dependencies could be found, or
71 "undef" on error.
72
73 minimum_syntax_version $limit
74 The "minimum_syntax_version" method will explicitly test only the
75 Document's syntax to determine it's minimum version, to the extent that
76 this is possible.
77
78 It takes an optional parameter of a version object defining the lowest
79 known current value. For example, if it is already known that it must be
80 5.006 or higher, then you can provide a param of qv(5.006) and the
81 method will not run any of the tests below this version. This should
82 provide dramatic speed improvements for large and/or complex documents.
83
84 The limitations of parsing Perl mean that this method may provide
85 artificially low results, but should not artificially high results.
86
87 For example, if "minimum_syntax_version" returned 5.006, you can be
88 confident it will not run on anything lower, although there is a chance
89 that during actual execution it may use some untestable feature that
90 creates a dependency on a higher version.
91
92 Returns a version object, false if no dependencies could be found, or
93 "undef" on error.
94
95 minimum_external_version
96 WARNING: This method has not been implemented. Any attempted use will
97 throw an exception
98
99 The "minimum_external_version" examines code for dependencies on other
100 external files, and recursively traverses the dependency tree applying
101 the same tests to those files as it does to the original.
102
103 Returns a "version" object, false if no dependencies could be found, or
104 "undef" on error.
105
106 version_markers
107 This method returns a list of pairs in the form:
108
109 ($version, \@markers)
110
111 Each pair represents all the markers that could be found indicating that
112 the version was the minimum needed version. @markers is an array of
113 strings. Currently, these strings are not as clear as they might be, but
114 this may be changed in the future. In other words: don't rely on them as
115 specific identifiers.
116
117BUGS
118 Perl::MinimumVersion does a reasonable job of catching the best-known
119 explicit version dependencies.
120
121 However it is exceedingly easy to add a new syntax check, so if you find
122 something this is missing, copy and paste one of the existing 5 line
123 checking functions, modify it to find what you want, and report it to
124 rt.cpan.org, along with the version needed.
125
126 I don't even need an entire diff... just the function and version.
127
128TO DO
129 Write lots more version checkers
130
131 - Perl 5.10 operators and language structures
132
133 - Three-argument open
134
135 Write the explicit version checker
136
137 Write the recursive module descend stuff
138
139 _while_readdir for postfix while without brackets
140
141 Check for more 5.12 features (currently only detecting "package NAME
142 VERSION;", "...", and "use feature ':5.12'")
143
144SUPPORT
145 All bugs should be filed via the CPAN bug tracker at
146
147 <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Perl-MinimumVersion>
148
149 For other issues, or commercial enhancement or support, contact the
150 author.
151
152AUTHORS
153 Adam Kennedy <adamk@cpan.org>
154
155SEE ALSO
156 perlver - the command-line script for running "Perl::MinimumVersion" on
157 your code.
158
159 Perl::MinimumVersion::Fast - another module which does the same thing.
160 It's a lot faster, but only supports Perl 5.8.1+.
161
162 <http://ali.as/>, PPI, version
163
164REPOSITORY
165 <https://github.com/neilbowers/Perl-MinimumVersion>
166
167COPYRIGHT
168 Copyright 2005 - 2014 Adam Kennedy.
169
170 This program is free software; you can redistribute it and/or modify it
171 under the same terms as Perl itself.
172
173 The full text of the license can be found in the LICENSE file included
174 with this module.
175
176