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0 pointsmanv13y ago0 comments

PDF is a subset of Postscript, which is a full-blown programming language disguised as a page description language.

People who think of the format as "adversarial" are wrong. Adobe never gave a shit about being adversarial in that sense.

The problem is that PDF is not a file format, it's a defined subset of a programming language (PostScript) used for portable rendering with fidelity. It's portable, in the sense that it should render the same way on whatever device it's rendered on (printed on a page or mastered to a display). And it's portable because it doesn't allow any postscript job-level commands, and it tries to ensure that each PDF File is standalone and can be concatenated together into a multi-page document or embedded in another document.

Postscript (and PDF) are also postfix, which can be confusing.

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hanche3y ago

> PDF is a subset of Postscript

That’s a bit of an oversimplification. There’s a whole layer of structure atop the postscript subset. Much software deals only with that layer, never looking into the chunks of rendering code. That’s plenty complicated already!

> Postscript (and PDF) are also postfix, which can be confusing.

I handwrote quite a bit of postscript wsy back when. It wasn’t that bad, really, you just had to keep the state of the stack firmly in your head. Being used to HP scientific calculators helped. I would never dream of handwriting a pdf file, though. Even the low level parts are harder to deal with, since most command names have been shortened to a single letter for efficiency.

jjgreen3y ago

Postfix is fine, you get used to it fairly quickly. But when you've finished and want to go the the toilet, you walk there backwards.

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