clarify dynamic prereqs in docs

[p5sagit/JSON-MaybeXS.git] / lib / JSON / MaybeXS.pm

diff --git a/lib/JSON/MaybeXS.pm b/lib/JSON/MaybeXS.pm
index 41b0d0d..457a955 100644 (file)
--- a/lib/JSON/MaybeXS.pm
+++ b/lib/JSON/MaybeXS.pm
@@ -4,7 +4,7 @@ use strict;
 use warnings FATAL => 'all';
 use base qw(Exporter);
 
-our $VERSION = '1.003007';
+our $VERSION = '1.003008';
 $VERSION = eval $VERSION;
 
 sub _choose_json_module {
@@ -274,6 +274,23 @@ Alternatively, you can use duck typing:
     use Moose::Util::TypeConstraints 'duck_type';
     is 'json' => ( isa => Object , duck_type([qw/ encode decode /]));
 
+=head1 INSTALLATION
+
+At installation time, F<Makefile.PL> will attempt to determine if you have a
+working compiler available, and therefore whether you are able to run XS code.
+If so, L<Cpanel::JSON::XS> will be added to the prerequisite list, unless
+L<JSON::XS> is already installed at a high enough version. L<JSON::XS> may
+also be upgraded to fix any incompatibility issues.
+
+Because running XS code is not mandatory and L<JSON::PP> (which is in perl
+core) is used as a fallback backend, this module is safe to be used in a suite
+of code that is fatpacked or installed into a restricted-resource environment.
+
+You can also prevent any XS dependencies from being installed by setting
+C<PUREPERL_ONLY=1> in F<Makefile.PL> options (or in the C<PERL_MM_OPT>
+environment variable), or using the C<--pp> or C<--pureperl> flags with the
+L<cpanminus client|cpanm>.
+
 =head1 AUTHOR
 
 mst - Matt S. Trout (cpan:MSTROUT) <mst@shadowcat.co.uk>