This is really interesting, because until I saw this comment I was thinking it was a North American/British thing.

So, to quote the wombat's example, you would spell the answer to the question, 'will you buy some milk?' as 'All right'?
Because I can't make those two words make sense, in that context.

apart from in The Damned's song 'I Feel Alright', which [is] not something that could be spelt any other way
Actually, from the point of view of making sense, I could see that split into two words.