I am trying to get better at metapost, but the error messages are pretty cryptic (if there are at all) and it always takes a big effort go compile an mp file. Up 'best' program for writing and compiling mp so far is http://www.tlhiv.org/mppreview/. It does provide some error messages but most of them are not useful.
What program do you use for writing/debugging your metapost code?
Is there a good IDE for writing metapost (that e.g. checks syntax and automatically updates a preview)?
MP seems to be such a nice thing but it seems for beginners it is incredibly complicated to get into.