common-lisp,parenscript , Is there a way to insert raw javascript in parenscript code?


Is there a way to insert raw javascript in parenscript code?

Question:

Tag: common-lisp,parenscript

The following code inserts third-party generated javascript as a string which will need to be eval'ed.

(ps (let ((x (lisp (json:encode-json-alist-to-string
                 '((:a . 1) (:b . 2))))))))

"(function () {
   var x = '{\"a\":1,\"b\":2}';
    return null; })();"

Is there a way to tell parenscript to insert a string unquoted?


Answer:

Added this to parenscript's non-cl.lisp file:

(define-expression-operator lisp-raw (lisp-form)
  `(ps-js:escape
    ,lisp-form))

(defun lisp-raw (x) x)

Result:

(ps (let ((x (ps::lisp-raw (json:encode-json-alist-to-string
                 '((:a . 1) (:b . 2))))))))
"(function () {
    var x = {\"a\":1,\"b\":2};
    return null;
})();"

Related:


Common Lisp - Writing a function that detects circular lists


list,function,recursion,lisp,common-lisp
I have an assignment for my CS functional languages class where we must write a function able to detect whether or not a given list is circular at its beginning. The function has to be recursive. Let's name it circular : * (setf list1 '(a b c d)) * (rplacd...

sbcl run-program hang when there is large amount of output from program


common-lisp,hang,sbcl
Recently I find a run-program hang issue of sbcl 1.2.7 (32bits, linux). The code as following (progn (with-open-file (s "test.out" :direction :output :if-exists :supersede) (loop repeat 900 do (write-line (make-string 76 :initial-element #\x) s))) (run-program "/bin/bash" (list "-c" "cat test.out") :output :stream)) That is when the "cat test.out" produce many...

Common Lisp - Giving &rest Lists as Arguments


arguments,lisp,common-lisp,sbcl
As a result of musings around an exercism problem, I am trying to write a function that takes an input number and an arbitrary length list of divisors to test, along with the expected divisibility (i.e. remainder 0) as a boolean, returning true if all expectations are met (defaulting to...

Char Comparison in Common Lisp


sorting,char,comparison,lisp,common-lisp
How can i compare characters with Common Lisp? I have google it and found out that there are some functions to do the comparison, like char=, char/=, char<, char>, char<=, and char>=. But, i can't use all of the functions just like: (char= 'a 'a) (char< 'a 'b) If i...

What does the non-terminating-p argument of set-macro-character do?


macros,common-lisp
Set-macro-character has an optional argument called non-terminating-p. It seems to be used to indicate whether another character should be read after reading the macro character, but the reader algorithm seems to ignore this argument. Is there a difference whether I set it to true or false?

Weird non-lisp errors with capturing labels with a lambda and `reduce`


lambda,crash,closures,common-lisp,allegro-cl
I stumbled across a very weird bug (?) while I was developing an application in Allegro Common Lisp, v9.0 for Windows. I do not get the regular lisp errors, instead I get system errors encapsulated in a lisp condition. I managed to create a simple test-case to reproduce the error...

Structuring large Lisp applications


lisp,common-lisp,quicklisp,asdf
I am currently trying to wrap my head around packages, systems & co. I now have read Packages, systems, modules, libraries - WTF? a few times, and I think I'm still having difficulties to get it right. If I simply want to split a Lisp source file into two files,...

Not numeric atoms LISP


lisp,common-lisp
I want to ask why this function doesn't work... (defun nenum(ls) (cond ((null ls) nil) ((listp car(ls)) (nenum (rest ls))) ((numberp car(ls)) (nenum (rest ls))) (t (cons (car ls) (nenum (rest ls)))))) Example: (nenum '(l 1 i (b) (5) s -2 p)) --> (l i s p) Thank you!...

What does backtick mean in LISP?


lisp,common-lisp,backticks
I have this macro, which rewrites define. If I remove the " ` " backtick it won't work. What is the explanation? (defmacro define ((name &rest r) body) `(defun ,name ,r ,body)) ...

How would I get the min/max of a list using a key


lisp,common-lisp
I currently have a list of objects, each containing a certain attribute. I would like to get the element of the list with the min attribute value. Is there a concise way of doing this? The python equivalent would be something like: min(d, key=d.get) Is there a way of getting...

Macro that defines functions whose names are based on the macro's arguments


macros,common-lisp,symbols,sbcl
*Note: Despite having frequented StackOverflow for a long time, this is the first question that I have posted myself. Apologies if it's a bit verbose. Constructive criticism appreciated. When I define a struct in Common Lisp using defstruct, a predicate function is automatically generated that tests whether its argument is...

Backquote String Interpolation


macros,lisp,common-lisp
Is it possible to use lisp's macro to do string interpolation? For instance, can I make a macro like this: (defmacro test (a) `",a") So that (test abc) returns "abc" as a string? I could probably cheat by quoting it and turning that quote into a string, but that doesn't...

Common-LISP debugging (code included)


debugging,lisp,common-lisp
I hope to get a quick fix to my code, which takes in a list of numbers, numberlist, and a threshold and return the number of items in numberlist that are greater than threshold. I just can't figure out what's wrong, and I am not familiar with debugging. I am...

If strings are vectors, why are they immutable?


lisp,common-lisp
if strings are vectors of characters, and a vector's elements can be accessed using elt, and elt is setf-able - then why are strings immutable?

How to move a file in Lisp using rename-file


lisp,common-lisp,pathname
What's the best way to move a file in Lisp in an implementation-independent way? For example I have an image file: (setq oldpath #P"SERVER:PICTURES;TEMP;PHOTO.PNG") and I want to move it out of the TEMP directory into the PICTURES directory. This seems to work: (setq newpath (make-pathname :host (pathname-host oldpath) :directory...

No-argument (and) returns t


clojure,scheme,lisp,common-lisp
Both CL and Scheme define (and) to return t (or #t) with no arguments. I'm trying to understand the rationale for this. My naive assumption is that an empty set is false, and passing in zero arguments feels like passing in nothing that can be true. Edit: clojure follows the...

Understanding “let” expression in LISP


lisp,common-lisp,let
I am extremely new to lisp, had previous experience with functional programming (Haskell, SML). Why is this code returning 14, and not 10 (ie. 1 + 2y + 3 + 1)? (defvar x 1) (defun g (z) (+ x z)) (defun f (y) (+ (g 1) (let ((x (+ y...

LISP: read number from user and commpare with array index


functional-programming,lisp,common-lisp
Hello guys I'm new In functional programming Really it is not Clear for me anyone can help me ? My Question just for getting the philosophy of writing on Functional programming language for example how I can write a program in Lisp language for reading the user inputs and compare...

Why does lisp use gensym and other languages don't?


lisp,common-lisp
Correct me if I'm wrong, but there is nothing like gensym in Java, C, C++, Python, Javascript, or any of the other languages I've used, and I've never seemed to need it. Why is it necessary in Lisp and not in other langauges? For clarification, I'm learning Common Lisp.

What is a common-lisp analogue of python's argparse?


python,common-lisp,argparse
What is a common-lisp analogue of python's argparse library for parsing command-line arguments?

lisp: dynamic scope vs explicit parameter passing


design-patterns,coding-style,common-lisp,anti-patterns,dynamic-scope
I see two different patterns for "output" functions in (common) lisp: (defun implicit () (format t "Life? Don't talk to me about life!")) (defun explicit (stream) (format stream "This will all end in tears.")) (defun test-im-vs-ex-plicit () (values (with-output-to-string (stream) (let ((*standard-output* stream)) (implicit))) (with-output-to-string (stream) (explicit stream)))) Is using...

Running compiled lisp program with clisp-2.49 on OS X


common-lisp,clisp
I have just started out programming in Common Lisp using GNU clisp-2.49 (compiled from source) as my implementation on OS X 10.10 Yosemite. I've written a simple "Hello World" program as follows: (EXT:SAVEINITMEM "test" :INIT-FUNCTION 'main :EXECUTABLE t) (defun main () (format t "Hello World!") (EXT:EXIT)) When I run: $...

Creating A Process Queue in Common Lisp


common-lisp
I have a server running Hunchentoot (CentOS and SBCL). When a user submits a specific type of post request, a subprocess is launched (run-program) which can take up to four minutes to complete. If five people perform that specific type of request at the same time, the server runs out...

How to Call a Go Program from Common Lisp


common-lisp
I have a Go program which cannot be rewritten in Common Lisp for efficiency reasons. How can I run it via Common Lisp? Options so far: 1. CFFI Using the foreign function interface seems to me like the "correct" way to do this. However, the research I did lead directly...

Dynamic 2d array in lisp


common-lisp,clisp
I want to have a 2D array in Lisp . But each row can have different number of elements(At max 5). So I thought of maintaining another single list to store the current sizes of each row, and update them whenever required. So, my code goes like this : (setq...

EVAL/APPLY: too many arguments given to F


lisp,common-lisp,clisp
Hello why do i get *** - EVAL/APPLY: too many arguments given to F on function call with nested lists parameter. I cannot figure it out, since I passed a simple nested list. (defun f (L) (cond ((NULL l) nil) ((listp (car L)) (append (F(car L))) (F(cdr L) (car (F...

Is there a way to insert raw javascript in parenscript code?


common-lisp,parenscript
The following code inserts third-party generated javascript as a string which will need to be eval'ed. (ps (let ((x (lisp (json:encode-json-alist-to-string '((:a . 1) (:b . 2)))))))) "(function () { var x = '{\"a\":1,\"b\":2}'; return null; })();" Is there a way to tell parenscript to insert a string unquoted?...

Local dynamic binding in common lisp


closures,common-lisp,dynamic-binding
Honnestly, I'm not sure I fully understand what it means for a binding to be "dynamic" versus "lexical". But I understand that when I use defvar or defparameterto define a binding, 1. it declares a global variable 2. the binding is declared "special", so that it can be shadowed by...

Custom slot options don't apply any reduction to its argument


common-lisp,clos,mop
Say if I define a metaclass that enhances standard slots with a validator slot, when I pass :validator (clavier:valid-email "The email is invalid") as an option, instead of storing the result of of the expression, which is a funcallable, it stores the expression itself. Am I'm missing a step when...

Trying to multiply all elements in a list of sublists with elements in another list in lisp


list,common-lisp
I'm trying to multiply a list with n sublists with a list with n scalars. It's supposed to work like this: (kmult-matrix '((3 4 2 4) (2 5 6 9) (1 -2 8 10)) '(2 3 5)) => ((6 8 4 8) (6 15 18 27) (5 -10 40 50))...

Read input into string in Lisp reader macro


macros,common-lisp,reader-macro
I am trying to make a reader macro that would convert @this into "this". This is what I currently have: (defun string-reader (stream char) (declare (ignore char)) (format nil "\"~a\"" (read-line stream t nil t)) ) (set-macro-character #\@ #'string-reader ) The problem is that this requires that I put a...

How do I best save/read data structures?


common-lisp,clos
I want to write some data structures pointed to by FOO and BAR to a file, and to read the data structures back into the symbols FOO and BAR when I start a new session of Common Lisp. It would appear *PRINT-READABLY* allows objects to be printed in a fashion...

SBCL: Deploying Hunchentoot application as executable


common-lisp,executable,sbcl,hunchentoot
Dear StackOverflow community, I started playing with SBCL Common Lisp and want to develop a small web application using Hunchentoot. For easy deployment I planned to save everything in a binary using sb-ext:save-lisp-and-die as I can live with the big output size. For the executable you need to supply a...

lisp remove a the content of one list from another list


lisp,common-lisp
I have a list of string like this called F: ("hello word i'am walid" "goodbye madame") => this list contain two elements of string and I have another list call S like this ("word" "madame") => this contain two words now I want to remove the elements of the list...

Long integer to string and vice versa, operation with digits


common-lisp,sbcl
Solving the Euler project problems I get that I need to make operations with the digits of a long number normally as a string. I work in linux, emacs, slime with sbcl. For example, to get the sum of the digits of this power 2¹⁰⁰⁰, I work this way, 1)...

Insertion into a list doesn't reflect outside function whereas deletion does?


list,lisp,common-lisp
I am new to Lisp. Deletion of an item in a list by a function gets reflected outside the function but insertion doesn't. How can I do the same for insertion? For example (defun test (a b) (delete 1 a) (delete 5 b) (append '(5) b) (member '5 b)) (setq...

EMACS-Live + Slime error at startup


emacs,common-lisp,slime,kubuntu
Ok, I must be missing something obvious. I'm getting stuck since yesterday to launch Emacs-live + slime. I'm using EMACS 24.3.1, installed Emacs-live and it worked well (if I start emacs-live without Slime it works), downloaded Slime-Pack from git and added this line to .emacs-live.el (live-append-packs '(~/.live-packs/slime-pack/)) I'm on a...

Common Lisp Object System method execution order


lisp,common-lisp,clos
I have the following two classes: (defclass person () ()) (defmethod speak ((s person) string) (format t "-A" string)) (defmethod speak :before ((s person) string) (print "Hello! ")) (defmethod speak :after ((s person) string) (print "Have a nice day!")) (defclass speaker (person) ()) (defmethod speak ((i speaker) string) (print "Bonjour!"))...

pathnames in Common Lisp, filenames with wildcards in them


common-lisp,filenames,wildcard,clisp,pathname
The characters * and ? are used as wildcards in pathnames. How does one refer to a filename that has ? as one of its actual characters? For example: [18]> (wild-pathname-p #p"foo") NIL [19]> (wild-pathname-p #p"foo?") T So referring to the filename "foo?" cannot be done this way. I tried...

How to use a parameter in a macro call?


macros,lisp,common-lisp,sbcl
I have defined the following simple macro: (defmacro define-class (class-name) `(defclass ,class-name ()())) And now I want to use it in the following function: (defun create-data (mode) (define-class mode)) After compiling the last function I get the following message, the variable MODE is defined but never used. And when I...

where is the text printed by C printf


io,common-lisp,cffi
I happened encounter a trouble with calling C printf function from SBCL via cffi. The problem is when I call printf function, I can't find the output text, just the return value of printf function show on the REPL. But when I quit SBCL, the output text appears on the...

Updating the window in response to CLIM frame commands


common-lisp,clim,mcclim
While trying to figure out CLIM, I ran into this example program. It's a simple maze game. The author claims to have tested it in LispWorks (and even has #+Genera in there, implying that this program would work on a real Lisp Machine), but I'm trying to get it working...

Modify list and return it inside a function in lisp


lisp,elisp,common-lisp
(defun testthis (node index newvalue) (set-nth node index newvalue) node ) I would like to modify the nth element of a list in a function and then returns this list to save the modification performed. How can I do a such function in lisp?...

Get element from list of list in lisp


lisp,elisp,common-lisp
I am a beginner with lisp. I manipulate list of list: ((name1, second) (name2, second2)) The goal of my function is to get the second element of the list that have name as it first node. For example: my list is: ((name1, second1) (name2, second2)) getelement list name1 should return...

SBCL: Gather output of run-program process while running


subprocess,common-lisp,sbcl
Dear StackExchange members, I recently began toying around with Common Lisp and want to create a web interface for administrating a modded Minecraft server. I already tried out this solution but in this case the function just hangs and never returns. My code looks like this: (defvar *proc*) (defun create-minecraft-proc...

How to use FFI:def-call-in in clisp


lisp,common-lisp,ffi,clisp
I have figured out how to make use of shared objects created from C code into Clisp using FFI:def-call-out but I am not able to figure out how to use FFI:Def-call-in. I don't know the process and actually I am confused if clisp will also create some .so file that...

Need help getting CLisp to read standard input into a list


python,lisp,common-lisp,clisp
I'm working on converting some existing Python code to CLisp just as an exercise ... The program reads a list of numbers and creates mean, min, max and standard deviation from the list. I have the file-based function working: (defun get-file (filename) (with-open-file (stream filename) (loop for line = (read-line...

Invalid specialized parameter in method lambda list


lisp,common-lisp
I am trying to write a simple coin flip program in Common Lisp. This is the code I have (defun yn (let ht (random 1) (if (eq ht 1) (princ heads) (princ tails)) ) ) It seems simple enough, but I keep getting the error: "Invalid specialized parameter in method...

How are `tagbody` and `go` implemented under the hood in Common Lisp?


compiler-construction,common-lisp
How are tagbody and go implemented in Common Lisp? Is it some form of setjmp/longjmp or is there a more elegant way of handling this? I'm writing a lispy language implemented in C and would like to have something like this....