typo fix in docs

[p5sagit/Import-Into.git] / lib / Import / Into.pm

diff --git a/lib/Import/Into.pm b/lib/Import/Into.pm
index 3314ec3..74b7358 100644 (file)
--- a/lib/Import/Into.pm
+++ b/lib/Import/Into.pm
@@ -8,21 +8,25 @@ our $VERSION = '1.001001'; # 1.1.1
 sub _prelude {
   my $target = shift;
   my ($package, $file, $line)
-    = $target =~ /[^0-9]/ ? ($target) : caller($target + 1);
+    = $target =~ /[^0-9]/ ? ($target) : caller($target + 2);
   qq{package $package;\n}
     . ($file ? "#line $line \"$file\"\n" : '')
 }
 
+sub _make_action {
+  my ($action, $target) = @_;
+  eval _prelude($target).qq{sub { shift->$action(\@_) }}
+    or die "Failed to build action sub to ${action} for ${target}: $@";
+}
+
 sub import::into {
   my ($class, $target, @args) = @_;
-  eval _prelude($target) . '$class->import(@args); 1'
-    or die $@;
+  _make_action(import => $target)->($class, @args);
 }
 
 sub unimport::out_of {
   my ($class, $target, @args) = @_;
-  eval _prelude($target) . '$class->unimport(@args); 1'
-    or die $@;
+  _make_action(unimport => $target)->($class, @args);
 }
 
 1;
@@ -39,11 +43,13 @@ Import::Into - import packages into other packages
 
   use Thing1 ();
   use Thing2 ();
+  use Thing3 ();
 
   sub import {
     my $target = caller;
     Thing1->import::into($target);
     Thing2->import::into($target, qw(import arguments));
+    Thing3->import::into(1); # import to level
   }
 
 Note: you don't need to do anything more clever than this provided you
@@ -69,6 +75,11 @@ C<import::into> on it. This is a global method, and is callable on any
 package (and in fact on any object as well, although it's rarer that you'd
 want to do that).
 
+If you provide C<import::into> with an integer instead of a package name, it
+will be used as the number of stack frames to skip to find where to export to.
+This has the advantage of preserving the apparent filename and line number
+being exported to, which some modules (L<autodie>, L<strictures>) check.
+
 Finally, we also provide an C<unimport::out_of> to allow the exporting of the
 effect of C<no>:
 
@@ -125,7 +136,7 @@ know if something's a pragma, and second that you can't use either of
 these approaches alone on something like L<Moose> or L<Moo> that's both
 an exporter and a pragma.
 
-So, the complete solution is:
+So, a solution for that is:
 
   my $sub = eval "package $target; sub { shift->import(\@_) }";
   $sub->($thing, @import_args);
@@ -134,6 +145,20 @@ which means that import is called from the right place for pragmas to take
 effect, and from the right package for caller checking to work - and so
 behaves correctly for all types of exporter, for pragmas, and for hybrids.
 
+Additionally, some import routines check the filename they are being imported
+to.  This can be dealt with by generating a L<#line directive|perlsyn/Plain
+Old Comments (Not!)> in the eval, which will change what C<caller> reports for
+the filename when called in the importer. The filename and line number to use
+in the directive then need to be fetched using C<caller>:
+
+  my ($target, $file, $line) = caller(1);
+  my $sub = eval qq{
+    package $target;
+  #line $line "$file"
+    sub { shift->import(\@_) }
+  };
+  $sub->($thing, @import_args);
+
 Remembering all this, however, is excessively irritating. So I wrote a module
 so I didn't have to anymore. Loading L<Import::Into> creates a global method
 C<import::into> which you can call on any package to import it into another