If you really want a solution and want it now, here is a solution using the unix-based m4 text/macro processor -- don't know if this has been mentioned in the other threads on this topic. It should be possible to write a file like so (maybe named *YourFile.elm.m4*):
## The following is the only line that lists the state names! define(`stateList', ``Alabama', `Alaska', `Arizona', `Arkansas'')dnl type AState = m4AltSep(stateList) allAStates = m4ListStates(stateList) allAStateNames = m4ListStrings(stateList) When you run it through m4 with the right macro definitions, you will get this: ## The following is the only line that lists the state names! type AState = Alabama | Alaska | Arizona | Arkansas allAStates = [ Alabama, Alaska, Arizona, Arkansas ] allAStateNames = [ "Alabama", "Alaska", "Arizona", "Arkansas" ] And the required definitions are (maybe this can be in *elmdefs.m4*): define(`m4foreach',`ifelse(eval($#>2),1, `pushdef(`last_$1',eval($#==3))dnl `'pushdef(`$1',`$3')$2`'popdef(`$1')dnl `'popdef(`last_$1')dnl `'ifelse(eval($#>3),1,`$0(`$1',`$2',shift(shift(shift($@))))')')')dnl define(`m4AltSep', `m4foreach(`xstate', `xstate`'ifelse(last_xstate,0,` | ')',$@)')dnl define(`m4ListStates', `[ m4foreach(`xstate', `xstate`'ifelse(last_xstate,0,`, ')',$@) ]')dnl define(`m4ListStrings', `[ m4foreach(`xstate', `"xstate"`'ifelse(last_xstate,0,`, ')',$@) ]')dnl The macros are adapted from M. Breen's page <http://mbreen.com/m4.html#toc5> especially the section on loops. The command that makes it work: cat elmdefs.m4 YourFile.elm.m4 | m4 > YourFile.elm The price you pay is having to somehow integrate this command into your build flow -- it is easy enough using unix *make*. And if your build tool would need to understand that when the .elm.m4 file changes, the .corresponding elm file should be rebuilt. And of course if you are using elm-format that will work at the .elm level and it will not understand the .elm.m4 level. Finally because it is a source-level modification, it does not resolve any of the semantic issues that have been raised in this thread. It just deals with the very narrow enum case. Given this extra work to set this up, some may opt to just live with the risk of getting your lists/enumerations out of sync, ... this can only be practical when your codebase has a lot of Enums like this which need to be kept in sync. -- You received this message because you are subscribed to the Google Groups "Elm Discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to elm-discuss+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
