It appears that Ddoc does not emit any documentation for manifest constants, even when they are marked public. I assume that this is a bug, since manifest constants are part of the public interface of a library.
There doesn't seem to be any problem with dmd 2.059 (Linux 64bits). This code: /// Defines the version of ImageMagick where these headers are based on. enum MagickLibVersion = 0x677; ///ditto enum MagickLibVersionText = "6.7.7"; Results in the folowing documentation: file:///home/mike/Projects/DMagick/docs/c/magickVersion.html
Indeed... turns out my code was completely wrong. I had accidentally used version (Ddoc) instead of version (D_Ddoc). Closing as invalid.