Jack Campin,

What you are describing is incorrect notation and the ABC standard does conform to the same standard as staff notation, so when ABC Navigator interprets A:|...B:| As AABAB it is perfectly correct. The only time a closing repeat does not need a matching opening repeat is if the repeat is back to the beginning of the piece, so in the case you have described, that is what the program does.

Just because

The vast majority of folk tunes in print use use

A:|
B:|

to mean AABB.

Does not make it right.

The correct form of notation in ABC for an AABB structure is A::B:| - the ABC standard allows you to simplify the strictly correct :||: to ::

When you are dealing with computer generated output such as converting ABC to MIDI, then it is essential you stick strictly to the standard or you will not get the results you expect and as you haven't stuck to the standard it is up to you, not the developer, to put it right.

to describe the developer as arrogant because he does not fix a "bug" that is not a bug is totally out of order. The developer is quite right in this instance not to change his program.