1Perl::MinimumVersion(3)User Contributed Perl DocumentatioPnerl::MinimumVersion(3)
2
6 Perl::MinimumVersion - Find a minimum required version of perl for Perl
7 code
8
10 # Create the version checking object
11 $object = Perl::MinimumVersion->new( $filename );
12 $object = Perl::MinimumVersion->new( \$source );
13 $object = Perl::MinimumVersion->new( $ppi_document );
14 # Find the minimum version
16 $version = $object->minimum_version;
17
19 "Perl::MinimumVersion" takes Perl source code and calculates the
20 minimum version of perl required to be able to run it. Because it is
21 based on PPI, it can do this without having to actually load the code.
22 Currently it tests both the syntax of your code, and the use of
24 explicit version dependencies such as "require 5.005".
25 Future plans are to also add support for tracing module dependencies.
27 Using "Perl::MinimumVersion" is dead simple, the synopsis pretty much
29 covers it.
30
32 new
33 # Create the version checking object
34 $object = Perl::MinimumVersion->new( $filename );
35 $object = Perl::MinimumVersion->new( \$source );
36 $object = Perl::MinimumVersion->new( $ppi_document );
37 The "new" constructor creates a new version checking object for a
39 PPI::Document. You can also provide the document to be read as a file
40 name, or as a "SCALAR" reference containing the code.
41 Returns a new "Perl::MinimumVersion" object, or "undef" on error.
43 Document
45 The "Document" accessor can be used to get the PPI::Document object
46 back out of the version checker.
47 minimum_version
49 The "minimum_version" method is the primary method for finding the
50 minimum perl version required based on "all" factors in the document.
51 At the present time, this is just syntax and explicit version checks,
53 as Perl::Depends is not yet completed.
54 Returns a version object, or "undef" on error.
56 minimum_explicit_version
58 The "minimum_explicit_version" method checks through Perl code for the
59 use of explicit version dependencies such as.
60 use 5.006;
62 require 5.005_03;
63 Although there is almost always only one of these in a file, if more
65 than one are found, the highest version dependency will be returned.
66 Returns a version object, false if no dependencies could be found, or
68 "undef" on error.
69 minimum_syntax_version $limit
71 The "minimum_syntax_version" method will explicitly test only the
72 Document's syntax to determine it's minimum version, to the extent that
73 this is possible.
74 It takes an optional parameter of a version object defining the the
76 lowest known current value. For example, if it is already known that it
77 must be 5.006 or higher, then you can provide a param of qv(5.006) and
78 the method will not run any of the tests below this version. This
79 should provide dramatic speed improvements for large and/or complex
80 documents.
81 The limitations of parsing Perl mean that this method may provide
83 artifically low results, but should not artificially high results.
84 For example, if "minimum_syntax_version" returned 5.006, you can be
86 confident it will not run on anything lower, although there is a chance
87 that during actual execution it may use some untestable feature that
88 creates a dependency on a higher version.
89 Returns a version object, false if no dependencies could be found, or
91 "undef" on error.
92 minimum_external_version
94 WARNING: This method has not been implemented. Any attempted use will
95 throw an exception
96 The "minimum_external_version" examines code for dependencies on other
98 external files, and recursively traverses the dependency tree applying
99 the same tests to those files as it does to the original.
100 Returns a "version" object, false if no dependencies could be found, or
102 "undef" on error.
103 version_markers
105 This method returns a list of pairs in the form:
106 ($version, \@markers)
108 Each pair represents all the markers that could be found indicating
110 that the version was the minimum needed version. @markers is an array
111 of strings. Currently, these strings are not as clear as they might
112 be, but this may be changed in the future. In other words: don't rely
113 on them as specific identifiers.
114
116 Perl::MinimumVersion does a reasonable job of catching the best-known
117 explicit version dependencies.
118 However it is exceedingly easy to add a new syntax check, so if you
120 find something this is missing, copy and paste one of the existing 5
121 line checking functions, modify it to find what you want, and report it
122 to rt.cpan.org, along with the version needed.
123 I don't even need an entire diff... just the function and version.
125
127 Write lots more version checkers
128 - Perl 5.10 operators and language structures
130 - Three-argument open
132 Write the explicit version checker
134 Write the recursive module descend stuff
136 Check for more 5.12 features (currently only detecting "package NAME
138 VERSION;", "...", and "use feature ':5.12'")
139
141 All bugs should be filed via the CPAN bug tracker at
142 http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Perl-MinimumVersion
144 <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Perl-MinimumVersion>
145 For other issues, or commercial enhancement or support, contact the
147 author.
148
150 Adam Kennedy <adamk@cpan.org>
151
153 <http://ali.as/>, PPI, version
154
156 Copyright 2005 - 2011 Adam Kennedy.
157 This program is free software; you can redistribute it and/or modify it
159 under the same terms as Perl itself.
160 The full text of the license can be found in the LICENSE file included
162 with this module.
163perl v5.12.3 2011-03-02 Perl::MinimumVersion(3)