Provide a ghc-tags.yaml file to make use of ghc-tags with Hledger easy.
ghc-tags is a standalone tool to replace the formerly-built-in
":ctags" feature (and I presume ":etags") in GHCi. These walked over
the source and produced a TAGS file (in vim-compatible ctags or
Emacs-compatible etags format) that allows the relevant editors to
quickly navigate around function definitions.
ghc-tags trips over some of the CPP used in Hledger. The solution
is to provide ghc-tags with explicit CPP defines via a YAML file.
However, if a YAML file is provided, one also must specify the source
paths, as the tool XORs config file | paths-on-command-line.
See <https://github.com/arybczak/ghc-tags/issues/6> for more
information.
Signed-off-by: Jonathan Dowland <jon@dow.land>