Twenty years ago I was working with EDI without XML. The format was a series of lines, each with a starting tag followed by a delimited list of values. Each tr

Twenty years ago I was working with EDI without XML. The format was a series of lines, each with a starting tag followed by a delimited list of values. Each transaction type had a grammar, so each starting tag could mean different things depending on its position within the grammatical structure of the transaction. We were new to EDI and had to roll out a bunch of partners fast, so we bought $60K software to help us. Turned out, that software had no understanding of the grammar; you had to use a cumbersome GUI to essentially write code from scratch to pull out what you wanted, with the only control structure available being GOTOs. Just pulling out a dozen important fields looked like a significant engineering effort. Then our partners said they required us to display to the user everything they sent. I ended up ditching the $60K software and writing my own tool with a proper parser, so I could input the grammar of a new transaction type in an hour and sort everything out right. After that it was easy. We didn't have to deal with brokers at least, we connected to everyone directly. I think the company became one of the brokers after I left.