I am trying to compile NPAPI plugin under Win-XP and VS 2008.
Its giving me error as nsScriptablePeer.obj : error LNK2019: unresolved external symbol _NPN_Evaluate referenced in function when I try to use NPN_Evaluate to call javascript function . I have added all libraries from xulrunner-sdk/lib and xullrunner-sdk/sdk/lib in additional library directories. Is there any other library needs to be included to use NPN_Evaluate function ?
The functions beginning with NPN_ are only accessible through the pointer passed during the initialization NP_Initialize phase. I've been caught by this situation and I decided to document a bit here.
In other words, you don't have to link a library but you have to catch the pointer to the NPN browser functions during the NP_Initialize call to your plugin.
You can find a brief rundown of npapi plugins in general here:
http://colonelpanic.net/2009/03/building-a-firefox-plugin-part-one/
it's a little disjointed, but my goal was to answer some of the not-well-explained parts of NPAPI, like the one you ran into here =]
Incidently, if you're using nsScriptablePeer, you're using an outdated example that still uses XPCOM instead of NPObjects. XPCOM will no longer be supported in future versions of firefox (starting 3.6, I believe)
A little more about that here: http://colonelpanic.net/2009/08/building-a-firefox-plugin-%E2%80%93-part-three/
Related
I have a project with some NPM deps, noteably "#grafana/data": "7.0.1". These dependencies bring in several other libs like apache-arrow. When I try to require deps via (require '"#grafana/data"), I get a bunch of compiler errors like:
ERROR: JSC_LANGUAGE_FEATURE. This language feature is only supported for ECMASCRIPT8 mode or better: async function.
I found similar kinds of errors addressed in google closure compiler issues which leads me to beleive that I cant have library dependencies that require modern javascript as the closure compiler can't handle them. Similarly the closurescript docs don't allow for a :language-in argument for es-2018 et. al.
The the clojure build.edn settings I set are:
:language-in :es-next
:language-out :es5
:rewrite-polyfills
Unfortunately, this doesn't work.
Is there any way that I can get the closure compiler to handle modern javascript dependencies? Are there some crazy hacks that I can do to make this work?
In my ClojureScript code I am requiring a JavaScript module called seedrandom which is in the node_modules folder, like this:
(ns something.core
(:require ["seedrandom" :as rnd]))
(js/console.log (.quick (rnd "x")))
According to the seedrandom documentation it is intended for both nodejs and the browser, and I've previously included and used it successfully in ClojureScript code via a <script> tag, confirming it works in the browser.
Running this cljs file in lumo on the command line works well and outputs a deterministically random number.
When I try to use this same cljs file in my Reagent frontend project I see the following error:
Compiling build :app to "public/js/app.js" from ["src" "env/dev/cljs"]...
events.js:183
throw er; // Unhandled 'error' event
^
Error: module not found: "crypto" from file /home/chrism/dev/something/node_modules/seedrandom/seedrandom.js
at onresolve (/home/chrism/dev/something/node_modules/#cljs-oss/module-deps/index.js:181:30)
...
Inside seedrandom.js we see the following:
// When in node.js, try using crypto package for autoseeding.
try {
nodecrypto = require('crypto');
} catch (ex) {}
Clearly this code is intended to ignore the built-in nodejs crypto module when running in the browser. The problem, as far as I can tell, is that the ClojureScript compiler does not know that - it sees that require('crypto') and tries to pull it into the compilation phase, but can't find it because it's a nodejs built-in.
Is there some way I can tell the compiler to ignore that particular require? Or can I shim the 'crypto' module somehow? What is the cleanest way to solve this?
Note: I have previously experienced this same issue with JavaScript modules which check for the fs node module. Hope we can find a general solution to use again in future. Thanks!
Relevant versions: [org.clojure/clojurescript "1.10.520"] and [reagent "0.8.1"].
This answer is related, asking a similar question from the perspective of Google Closure, which ClojureScript uses, but I'm looking for an answer I can use specifically with cljs.
I have a Clojurescript program running in the browser.
It imports a number of libraries, and then I want to allow the user to enter some small clojurescript "glue-code" that calls those libraries.
I can see (from https://cljs.github.io/api/cljs.js/eval) that you call eval with four arguments, the first being the state of the environment, which is an atom. But can I actually turn my current environment with all the functions I've required from elsewhere, into an appropriate argument to eval?
Update :
I thought that maybe I could set the namesspace for the eval using the :ns option of the third, opts-map, argument. I set it to the namespace of my application :
:ns "fig-pat.core"
But no difference.
Looking at the console, it's definitely the case that it's trying to do the evaluation, but it's complaining that names referenced in the eval-ed code are NOT recognised :
WARNING: Use of undeclared Var /square
for example. (square is a function I'm requiring. It's visible in the application itself ie. the fig-pat.core namespace)
I then get :
SyntaxError: expected expression, got '.'[Learn More]
Which I'm assuming this the failure of eval-ed expression as a whole.
Update 2 :
I'm guessing this problem might actually be related to : How can I get the Clojurescript namespace I am in from within a clojurescript program?
(println *ns*)
is just printing nil. So maybe Clojurescript can't see its own namespace.
And therefore the :ns in eval doesn't work?
Calling eval inside a clojurescript program is part of what is called "self-hosted clojurescript".
In self-hosted clojurescript, namespaces are not available unless you implement a resolve policy. It means that have to let the browser know how to resolve the namespace e.g. loads a cljs file from a cdn.
It's not so trivial to implement namespace resolving properly.
This is explained in a cryptic way in the docstring of load-fn from cljs.js namespace.
Several tools support namespaces resolving in self-host cljs running in the browser e.g Klipse and crepl
Using PhpStorm 8.0.3.
Let's say I have this function:
public function myFunction($argA, $argB) {
// ...
}
And I'm calling it from somewhere else in the project with one extra argument, like:
$myClass->myFunction($arg1, $arg2, $arg3);
I know this is not considered an error in PHP, and it can be useful in some scenarios... but it is wrong according to my own coding standards, so I just wanted to know if there's a way to make PhpStorm to warn me if I'm doing it somewhere...
You cannot do anything about it in PhpStorm v8.0.3.
But PhpStorm v9 already has separate inspection for that. If you want -- try v9 EAP build now.
According to documentation (https://developers.google.com/closure/compiler/docs/api-tutorial3#externs), it seems the closure compiler should rename variables when no external declaration exists, including when using functions/variables from an external bit of code. The example they give is
function makeNoteDom(noteTitle, noteContent, noteContainer) {
// Create DOM structure to represent the note.
var headerElement = textDiv(noteTitle);
var contentElement = textDiv(noteContent);
...
}
where the textDiv function is declared in the global scope by a third-party lib of some sort. It says textDiv should be declared external to prevent renaming.
My question is - when I put this code or similar into the Closure Compiler without any extern declarations why is textDiv not renamed (which would break the code), as the documentation indicates?
The compiler assumes that calls to an undefined function are in fact calls to an external functions. Using the command line compiler, you can use --warning_level VERBOSE to have the compiler treat this condition as an error.
The Web Application is primarily built for demos and assumes this by default. While you can set a VERBOSE warning level, it will not change this functionality. See the Additional Web Service Options page for information on options. I've filed a bug report about this.
Due to the renaming algorithm for properties, undeclared properties will be renamed in a breaking way if that same property name isn't declared on an object in externs.