从Erlang运行JS代码：如何为erlang_v8添加marked等JS库？

Hey there! I’ve tinkered with erlang_v8 a fair bit, so let me break down exactly how to add a library like marked to its V8 context. It’s straightforward once you know the steps—here’s what you need to do:

Step 1: Get the marked Library Code #

First, you’ll need a browser-compatible (UMD or global variable) build of marked. The easiest way is to grab the minified UMD version from its official releases. Save this file locally (say, marked.min.js) so your Erlang code can read it.

Step 2: Load the Library into the erlang_v8 Context #

Once you have the library file, you’ll read its content and evaluate it within your erlang_v8 context. This registers the marked function as a global variable in the V8 environment.

Here’s a complete Erlang code example:

% 1. Read the marked library source file
{ok, MarkedBinary} = file:read_file("/path/to/your/marked.min.js"),
MarkedSrc = binary_to_list(MarkedBinary),

% 2. Create a new V8 context
{ok, Ctx} = v8:new_context(),

% 3. Load the marked library into the context
case v8:eval(Ctx, MarkedSrc) of
    ok -> 
        % 4. Now use the marked function!
        {ok, HtmlResult} = v8:eval(Ctx, "marked('# Hello from erlang_v8! This is **bold** text.')"),
        io:format("Converted Markdown to HTML: ~s~n", [HtmlResult]);
    {error, Reason} ->
        io:format("Failed to load marked: ~p~n", [Reason])
end.

Key Notes #

• Use UMD/Global Builds: Avoid ES module versions of marked unless you confirm erlang_v8 supports ES modules (most older or embedded V8 setups don’t handle them out of the box).
• Reuse Contexts: If you need to use marked multiple times, keep the context alive instead of recreating it each time—this saves the overhead of reloading the library.
• Debugging: If you run into errors, use v8:eval/3 with the return_errors option to get detailed error messages from the V8 engine.

内容的提问来源于stack exchange，提问作者User590254