At one time, I became interested in the Turing-completeness of sed, and I started working on primitives for flow control and function calls. Then, I came to my senses.
There's an error in line 1024. The transform strings are not the same length.
I'd like to see more sed programs on HN instead of the usual Python, Ruby or Go offerings.
I wrote a sed version of the the Python script "youtube-dl". This way I don't need Python installed to download YouTube videos. And it's easy to edit if YouTube suddenly changes their "API"; no need to wait for someone else to fix their Python or Lua script. In truth, it's not pure sed though. It uses sh (not bash), sed and ftp (or any other http client that handles 302's).
I never need to install Python permanently.[1] In my experience, there is almost always a way to do what needs to be done with what UNIX provides, without installing more software. This keeps the system smaller, more standardized and hence more portable than one where various dependencies are haphazardly added.
1. Sometimes I have to install it temporarily, for "reverse engineering" a non-Python solution, e.g., when someone decides to use Python as a substitute for make.
Like sed, all UNIX systems provide ssh. It's not "extra software". There's no need to use telnet.
On the other hand, not all UNIX systems have Python pre-installed. Moreover, as in the case of embedded products, not all systems may have the space for it.
This is a bit like that fellow who did pixel art by manually writing coloured table cells in HTML in Notepad - very, very impressive, but it does make one wonder a little about the person who has done it.
After performing en passant the computer went crazy and the King started taking all the pieces between down row 8. I ended up with a very easy checkmate as I walked my pawn the remaining three rows, unfettered even when it was under double pressure from the night and queen.
I wonder if this is perhaps an issue caused by the fact I used OS X's BSD sed.
Edit: Hmm, can't seem to format it right. Anyways, the bug seems to be present in gnu sed as well. Really the whole game was screwy. I started with e2 e4 and it all went down hill from their for my opponent :).
Interesting. Either way my opening seemed to be more problematic as the computer still went out of its way to checkmate itself without the en passant. Still a cool achievement.
sed, and also awk, and ed, are worth learning. I mean coding a chess game in those tools is just a novelty, but you can do so much really useful text processing with just those tools, and they are pretty much guaranteed to be available on almost any *nix machine.
OK I'll bite. For this answer I'll assume "easily" to mean "with less typing".
ed has a more concise syntax for joining arbitrary lines of a file (by line number or pattern) and then saving the file (by way of a temp file in $TMPDIR). You could do this with awk and perhaps with other standard tools (note: I don't consider perl to be "standard"). But I think it's safe to say the ed script would always be shorter. ed's syntax for deleting and moving arbitrary lines is similarly concise. For these specific tasks, it's not going to be easy to win at code golf using awk or other tools... and in some cases it may be impossible.
I use sed in makefiles, to scrape the source code for a version number, and then embed that version number in the name of the executable to be built. That would be easy enough in, say, Python, but as a sed script it's lightweight, decently readable, and puts everything you need to know right there in the makefile.
That said, I've recommended learning Python to a few people, but have never even suggested anybody learn sed or awk.
Was going to comment the same thing. This seems like it could be really neat, but with all of the comments in a language I can't read, I'm not entirely sure what to think, haha.
I love how he felt compelled to excuse his omission of castling and en passant moves by explaining that they were added to chess "later" (14th and 15th century)... maybe he started working on this project before those rules were added? :)
