explain what an undef return value means

mojolicious · Mar 3, 2014 · 349482b · 349482b
1 parent 8d2fe50
commit 349482b
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Showing 2 changed files with 15 additions and 11 deletions.
diff --git a/lib/Mojo/JSON.pm b/lib/Mojo/JSON.pm
@@ -310,8 +310,9 @@ Mojo::JSON - Minimalistic JSON
 
   # Handle errors
   my $json = Mojo::JSON->new;
-  if (defined(my $hash = $json->decode($bytes))) { say $hash->{message} }
-  elsif (my $err = $json->error) { say "Error: $err" }
+  my $hash = $json->decode($bytes);
+  my $err  = $json->error;
+  say $err ? "Error: $err" : $hash->{message};
 
 =head1 DESCRIPTION
 
@@ -369,7 +370,8 @@ Encode Perl value to JSON.
   my $value = j($bytes);
 
 Encode Perl data structure (which may only be an C<Array> reference or C<Hash>
-reference) to JSON or decode JSON and return C<undef> if decoding fails.
+reference) to JSON or decode JSON, an C<undef> return value indicates a bare
+C<null> or that decoding failed.
 
 =head1 ATTRIBUTES
 
@@ -391,7 +393,8 @@ following new ones.
 
   my $value = $json->decode($bytes);
 
-Decode JSON to Perl value and return C<undef> if decoding fails.
+Decode JSON to Perl value, an C<undef> return value indicates a bare C<null>
+or that decoding failed.
 
 =head2 encode
 

diff --git a/lib/Mojo/Message.pm b/lib/Mojo/Message.pm
@@ -143,7 +143,7 @@ sub is_limit_exceeded { !!shift->{limit} }
 sub json {
   my ($self, $pointer) = @_;
   return undef if $self->content->is_multipart;
-  my $data = $self->{json} ||= j($self->body);
+  my $data = $self->{json} //= j($self->body);
   return $pointer ? Mojo::JSON::Pointer->new($data)->get($pointer) : $data;
 }
 
@@ -570,12 +570,13 @@ Check if message has exceeded L</"max_line_size"> or L</"max_message_size">.
   my $value = $msg->json;
   my $value = $msg->json('/foo/bar');
 
-Decode JSON message body directly using L<Mojo::JSON> if possible, returns
-C<undef> otherwise. An optional JSON Pointer can be used to extract a specific
-value with L<Mojo::JSON::Pointer>. Note that this method caches all data, so
-it should not be called before the entire message body has been received.
-The whole message body needs to be loaded into memory to parse it, so you have
-to make sure it is not excessively large.
+Decode JSON message body directly using L<Mojo::JSON> if possible, an C<undef>
+return value indicates a bare C<null> or that decoding failed. An optional
+JSON Pointer can be used to extract a specific value with
+L<Mojo::JSON::Pointer>. Note that this method caches all data, so it should
+not be called before the entire message body has been received. The whole
+message body needs to be loaded into memory to parse it, so you have to make
+sure it is not excessively large.
 
   # Extract JSON values
   say $msg->json->{foo}{bar}[23];