“Does the phrase ‘bloody mess’ do anything for you?” a lean woman with short black hair and piercing dark eyes asked from halfway down the table. “This thing is written in something that looks like a bastard version of Forth crossed with LISP and some features from C and Modula 2 thrown in for grins.”
“When do we get to meet this guy, anyway?” someone else asked. “I’d like to shake him warmly by the throat.”
“There may be a problem with that, My Lord,” Moira said from her place next to Jerry. “He went off alone into the Wild Wood and we have not yet found him.”
“We’re going to need him,” Nancy said. “Someone has got to explain this mess. Some of this code is literally crawling with bugs.”
“You mean figuratively,” Jerry corrected.
“I said literally and I mean literally,” she retorted. “I tried to run one routine and I got a swarm of electric blue cockroaches.” She made a face. “Four-inch-long electric blue cockroaches.”
“Actually the basic concept of the system is rather elegant and seems to be surprisingly powerful,” Karl said.
Nancy snorted.
“No, really. The basic structure is solid. There are a lot of kludges and some real squinky hacks, but at bottom this thing is very good.”
“I’ll give you another piece of good news,” Jerry told them. “Besides the Dragon Book, Wiz left notes with a lot of systems analysis and design. Apparently he had a pretty good handle on what he needed to do, he just didn’t have the time to do it. I think we can use most of what he left us with only a minimal review.”
“Okay, so far we’ve just been nibbling around the edges to get the taste of the thing. Now we’ve got to get down to serious work.”
“There’s one issue we’ve got to settle first,” Nancy said. “Catching errors.”
“What’s the matter, don’t you like electric blue cockroaches?” Danny asked.
“Cockroaches I can live with. They glow in the dark and that makes them easy to squash. I’m more concerned about HMC or EOI-type errors.”
“HMC and EOI?”
“Halt, Melt and Catch fire or Execute Operator Immediately.”
“One thing this system has is a heck of an error trapping system,” said Jerry.
“That is because the consequences of a mistake in a spell can be terrible,” Moira told him. “Remember, a spell is not a computer which will simply crash if you make an error.”
The people up and down the table looked serious, even Danny.
“Desk check your programs, people,” Jerry said.
“That’s not going to be good enough. There are always bugs, and bugs in this stuff can bite—hard. We need a better system for catching major errors.”
“There is one way,” Judith said thoughtfully.
“How?”
“Redundancy with voting. We use three different processors—demons—and they have to all agree. If they don’t the spell is aborted.”
“Fine, so suppose there’s a bug in your algorithm?”
“You use three different algorithms. Then you code each primitive three different ways. Say one demon acts like a RISC processor, another is a CISC processor and the third is something like a stack machine. We split up into three teams and each team designs its own demon without talking to any of the others.”
“That just tripled the work,” someone said.
“Yeah, but it gives us some margin for error.”
“I think we’ve got to go for the maximum safety,” Jerry Andrews said finally. “I don’t know about the rest of you, but I have no desire to see what a crash looks like from inside the system.”
“My Lord, you seem to have made remarkable progress,” Moira said as Jerry showed her through the programmers’ new quarters.
The team had settled in quickly. Each programmer got his or her own stall and trestle tables filled the center aisle. The stalls were full of men and women hunched over their trestle table desks or leafing through stacks of material. At the far end of the room Judith and another programmer were sketching a diagram in charcoal on the whitewashed barn wall.
“Once you get used to giving verbal commands to an Emac instead of using a keyboard and reading the result in glowing letters in the air, programming spells isn’t all that different from programming computers,” Jerry told her. “We’d be a lot further along if Wiz were available, but we’re not doing badly.”