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My Life as a Forth Interpreter (1986) [pdf]
- dimitar 13y agoWow, can someone explain this story? Its hard to follow if you are not a forth hacker.
- davidw 13y agoI think it has something to do with this: http://globalnerdy.com/wordpress/wp-content/uploads/2007/09/forth_on_the_atari.jpg http://globalnerdy.com/wordpress/wp-content/uploads/2007/09/...
- deleted 13y ago[deleted]
- nocoment 13y agoIt looks like an introduction to FORTH via Kafka.. There is a nice browser interpreter here: http://forthfreak.net/jsforth80x25.html http://forthfreak.net/jsforth80x25.html you can start with: 1 1 + . (+ adds, . prints and this is clearly reverse polish notation) FORTH is in essence an accumulator CPU like the 68000, except it has an easier abstraction to define new instructions (aka "Words") to act like the + or . above.
- emeraldd 13y agoIs that another term for a stack machine? I haven't heard of an accumulator cpu before ...
- nocoment 13y agoA CPU with an accumulator register (default locations that accepts the result for each instruction and is usually one of the operands in each new instruction.) I guess that is a bit less capable than an actual stack machine like FORTH but sort of the starting point of this programming mentality (at least as I think of it.)
- Someone 13y agoThe tokens coming in are the tokens from the user's ("Him") input. The outer interpreter is what translates those tokens into actions to perform. The inner interpreter performs those actions. In a Forth, both the inner and the outer interpreter are extremely simple. The story describes them in detail. Outer interpreter: look up token in dictionary/dictionaries. If found, instruct inner interpreter to execute it by giving it the address of the function that the token describes. If not found, try interpreting the word as a number in the current base. If that succeeds, push the number on the stack. If it fails, signal an error and clear some state. Inner interpreter: start reading at the address supplied. Recursively interpret every word read as address of another function until encountering a 'end of function' marker. Leo Brodie's variant of this story doesn't use the terms inner and outer interpreter because it was written before the names were invented, but it may be instructive, anyways: http://www.forth.com/starting-forth/sf1/sf1.html http://www.forth.com/starting-forth/sf1/sf1.html
- raverbashing 13y agoSo the inner interpreter is a VM of some sort? Outer interpreter looks like exactly that, an interpreter (as opposed to a compiler)
- Someone 13y agoYes, it has been described as such. A main difference/interesting property of this VM is that end users write programs in Forth by extending the VM's instruction set (= the set of dictionary definitions). While in interpreted mode or at compile time (i.e. when the user types words in the terminal), the instruction lookup is slow, through one or more linked lists. At run time, definitions simply consist of lists of pointers to other functions.
- etfb 13y agoFor context: the Computer Language magazine in the 1980s had a tradition of April Fools editions. This is from one of them, before they got too serious, changed their name to Software Development magazine, and blazed the way for Dr Dobbs into oblivion.
- TazeTSchnitzel 13y agoThat was brilliant. Now, how about "My Life as a Haskell Interpreter"?
- eru 13y agoThat would be interesting. And the cliff from Outer Interpreter to Compiler (instead of Inner Interpreter) would be even steeper.
- brianobush 13y agoanyone have a copy? link is dead.
- kevinchen 13y agoScribd seems to have it cached. Link reproduced here for convenience: http://www.scribd.com/doc/212732047/Untitled?secret_password=tdsvrimvut8x31rssyy#full http://www.scribd.com/doc/212732047/Untitled?secret_password...
- shellehs 13y agoI'm too late. It's 403 now. > You don't have permission to access /wp-content/extras/bph-publications/CompLang-1986-04-Hayes-Forth.pdf on this server. The site shows.
- mthq 13y agoThe site owner thinks he is being DDOS'ed: http://bit-player.org/2014/net-pests/ http://bit-player.org/2014/net-pests/
- bit-player 13y agoI'm the site owner. It's open again, temporarily. Somebody's script has multiple machines (many are EC2 instances) downloading the same file many times per second. That's not something I want to encourage.
- NoodleIncident 13y agoInteresting. I suppose an automated DDoS of everything on the hackernews front page isn't impossible. Are there other explanations? Scribd definitely got it automatically at least once, maybe they do it too many times? How many HN users use EC2-based proxies?
- zem 13y agovery nicely done indeed.
- bit-player 13y agoApologies to the HN community. I'm the author of the story linked to here. I'm also the jerk who pulled it off the web when I thought my site was getting the DDoS treatment. Mea culpa.