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20:58:07
pjb
puchacz: you can put reader macros on [-+0-9] so that you can read 1_000_000 ; also on _, because I would admit _123_456.
21:25:15
no-defun-allowed
are there any fancy (human) language parsers like prolog-talk in quicklisp?
21:48:15
no-defun-allowed
i'd like to take some english text, make it into a parse tree, and possibly turn it back later
21:54:38
no-defun-allowed
is there anything on using cl-nlp? i found tokenizing but just doing apropos on variable names doesn't seem too efficient
21:59:35
fiddlerwoaroof
margaritamike: using lquery, it would be something like this: (lquery:$ (initialize "<html><!--foo--></html>") (children) (contents) (filter #'plump:comment-p))
22:00:17
fiddlerwoaroof
lquery is a little dsl wrapper around plump that makes traversing xml a lot nicer
23:27:39
djeis[m]
The trouble is that parsing of the whole file happens before evaluation when you use compile.
23:28:12
margaritamike
What should I use instead of defvar for my my variable to load up after quickload has finished importing the library?
23:28:27
pjb
Indeed. ql:qiuckload is a function. This form is evaluated only when the file is loaded, not when it's compiled.
23:30:08
djeis[m]
You need the eval when if you want the ql:quickload to happen at compile time at all, which you do want because you need to be able to refer to the drakma package. That's why we usually use a build system like asdf to manage load-order lol
23:30:29
fiddlerwoaroof
you can do something like sbcl --eval '(ql:quickload :dependency)' --load my-script.lisp --eval '(my-script-package::main)' --quit instead
23:30:56
djeis[m]
You need the quickload to be evaluated before you compile the rest of the file is all.
23:31:06
pjb
Then asdf can take care of doing the things that need to be done at compilation time, vs. load-time.
23:31:58
no-defun-allowed
cl-earley-parser seems good enough for what i need, i just need to write the grammar and scrape a dictionary
23:32:12
djeis[m]
If you use load directly that might solve the issue, because it might (I forget exactly...) evaluate each form before it even parses the forms afterwards.
23:32:33
djeis[m]
But compile-file needs to parse the whole thing, and it won't go about evaluating stuff you haven't explicitly told it to.
23:34:42
margaritamike
I just want to load a file into slime and have it execute what i tell it to sequentially. I don't want to have to learn asdf if it's not required right now. Still getting a hang of quickload and drakma.
23:36:30
fiddlerwoaroof
margaritamike: if you insist, you want to do this: https://fwoar.co/pastebin/3c2b5cd1ddb15117de83096eff495b3091ccc00d.lisp.html
23:38:10
pillton
margaritamike: You want defparameter instead of defvar if you want to continue working this way.
23:39:06
fiddlerwoaroof
You could also do this: https://fwoar.co/pastebin/cecc07593809dea7daeff8b0ad4a4bd4c8f2a02c.lisp.html
23:41:23
margaritamike
I just want a variable to reference and pass the response on to a parser to search the DOM tree for random junk
23:42:26
pjb
Even if you write a script, it's important to write functions, and to call the main function at the end, avoiding to do anything else at the toplevel.
23:43:01
pjb
This is because scripts are read by buffer load, and if you are editing the script when it's executing, then you will read broken sexps across buffer boundaries!
23:43:43
Jachy
fiddlerwoaroof: I'd add #-quicklisp in front of the load, no need to load it again if you didn't run it as a script...
23:43:50
margaritamike
Why was the compiler not smart enough to tell me any of this. I would not have figured this stuff out from the stacktrace it gave me.
23:44:34
fiddlerwoaroof
margaritamike: the problem is you aren't really working the way CL expects you to work
23:45:13
pillton
margaritamike: Ok. SLIME starts a single lisp machine with a global environment. This global environment is updated every time you compile and/or load a file.
23:45:51
Jachy
margaritamike: What is it you want the compiler to tell you? Admittedly it's confusing at first to understand setf/defvar/defparameter and when it's appropriate to use them at the top level...
23:46:40
pillton
margaritamike: The first time you loaded the file you pasted, a dynamic variable was created for *response* and the value returned by (drakma:http-request "http://lisp.org") was bound to the *response* variable.
23:47:44
pillton
margaritamike: The second you loaded the file you pasted, the binding of the *response* variable was NOT updated because DEFVAR was used instead of DEFPARAMETER.
23:50:18
pillton
margaritamike: From clhs defvar you see "defparameter unconditionally assigns the initial-value to the dynamic variable named name. defvar, by contrast, assigns initial-value (if supplied) to the dynamic variable named name only if name is not already bound."
23:51:13
pillton
margaritamike: When in SLIME, you always have to remember that you are constantly mutating a single global environment.
23:52:16
margaritamike
This is why it seemed like there was some weird caching issue going on I guess xD
23:56:18
aeth
The most useful use of defvar that I have found is for something like this: (defvar *cache* nil) and then later on in your program (if (and *cache* cache-p) *cache* (really-expensive-computation-that-takes-a-minute))
23:56:48
Jachy
Stylistically (at least what i remember from PAIP) defvar indicates something meant to change in the running of the program with setf forms, defparameter indicates something more meant to change the overall behavior of the program, during the running it usually stays constant. i.e. a change to the parameter is a change to the program, while a change to a var is a change by the program.
23:56:52
aeth
With *cache* you can repeatedly run/debug your entire program from the start while working on it without having to repeat the expensive part.
0:01:51
aeth
I guess I could just have *cache* be unbound and then do (boundp '*cache*) instead. This might be more useful if you give it a type because instead of DECLAIMing the type (or null foo) you can just declaim the type to be foo and then no user can set it to NIL after it was already initialized once. But in my particular example you probably want to be able to let the user run it all again.
0:02:34
aeth
(This is, of course, assuming you are using an implementation that respects type declarations.)
0:10:49
aeth
Oh note that if you're using defvar you probably only want to use it in one location and set it in one location, if you don't want to wind up with unexpected results.
0:12:33
aeth
e.g. this is the only place where *cache* should show up (fixed): (if (and *cache* cache-p) *cache* (setf *cache* (really-expensive-computation-that-takes-a-minute)))
0:16:35
aeth
It essentially becomes the API function for that variable, which shouldn't be exported in the package.