Day 1453 – YACC – What Does It All Mean?

Friday January 1, 2021 (Happy New Year)

Election Day -59

20 Days until the Inauguration on January 20, 2021

Yesterday I entitled my screed – Time to Turn Over a New Leaf!

To which I say, “Naw.” In the best “Bah, Humbug” tradition.

I don’t want to rain on anybody’s parade, piss on it – maybe.

When I first got into computers a guy at Bell Labs had written YACC, which stands for “Yet Another Compiler Compiler.” In those days the Labs would document their work with a manual page explaining what the command did and oftentimes they would write a short paper which was included in a 3 ring binder of notes. In the short paper the programmer asked, “How many compile compilers do we need?”  It’s a  good question.

Compilers take one set of instructions (often called a computer language) and recode them into another set of instructions. Compiler compilers or cross-compilers do this between languages. Programmers found it easier to write a small amount of code that a new machine understood rather than rewriting all the code they had developed on an older machine. Think of it as using the same type of spark plug in a new car. If the old one works why remake it? 

The question of how many compiler compilers do we need is an interesting one in the sense of “How many times do we need to relearn the same stuff?” 

When I got into computers the way you did fancy printing was with NROFF or TROFF. At that time, or shortly before, IBM had these big bulky printers that were like manual typewriters but instead of having keys that struck the paper they had a chain with type on it. The chain whirled horizontally over the paper and a hammer came down to strike the printer chain at just the right time to impress the letter you wanted onto the paper. Yes there was a ribbon of ink in-between the paper and the type on the chain.

DEC Computers had figured out a way to format stuff on these printers and their program was called RUNOFF or ROFF for short. The idea was that they would hide in a file a series of wacky character combinations that would tell the computer what to do to format the printout. 

When I came along those printers were still in use as were other printers. One man at Bell Labs had taken the ROFF program and adopted it to a new operating system called UNIX. He called the program New ROFF or NROFF. All these printers had a fixed set of type. You couldn’t change fonts, but you could underline things by letting the chain printer whirl over the line a second time and have the underline character be hit. You could also BOLD things by having the same letter struck three times in the same place on the page. 

When typesetting printers came along, (ie those that you could change the font and font size) NROFF was extended to include those capabilities. The program was called TROFF, for Typesetting Run Off. 

The way all these programs worked was by placing character combinations starting usually in the first column of the file to tell the printer to do something. A “.B” in the first column would tell the printer to BOLD everything from here on out until it was told to stop or do something else. Those instructions are call “macros” and because they are placed in the actual text file therefore are called “in-line macros.”

I mention all this to say that when HTML came along and someone tried to explain to me that when the computer saw “<b>” it meant bold I said, “Oh, an in-line macro for bold.” I got the answer of, “No, no. See when it sees the <b> characters it knows to bold the print…” I smiled and thanked the person for their erudition.

Yesterday, I saw a car in the grocery store parking lot. It had a “LIBERTARIAN” bumper sticker and a “LEGALIZE FREEDOM” bumper sticker. I took a picture. As I got in my car this young man was gesturing at me. I stopped and rolled down my window.

“Why did you take a picture of my car?” he asked.

I thought for a split second. Much like the people who debate paper or plastic at the grocery store, and said, “I like you stickers.” 

He gave me a fist bump.

It wasn’t worth more. I had been here before.

I agree with Keith Obermann. The 140 Republican Congressmen who say the Electoral College vote should be overturned should not be seated and instead they should be prosecuted for sedition.

In my older age, I am mellowing. If when the Electoral College meets there is a mob of violent actors ready to overturn our democracy, I think they should meet the fate all traitors deserve. Just sayin’