Hacking VBA to support native scripting runtime with no COM dependencies

(github.com)

24 points | by n013 10 days ago ago

10 comments

  • moron4hire 3 days ago

    This will be really useful for my coworkers who get stuck in SCIFs with nothing but Excel available to them.

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  • blargthorwars 3 days ago

    Friendly reminder for MS Access fiends:

    It's ok to store code in tables and then pass it to VBA for evaluation via Eval, or to ASF via the engine.Compile

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    • cyanydeez 3 days ago

      But what if i want to debug my code?

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      • blargthorwars 3 days ago

        Great question! Programmatically copy your snippet to a module, then call it:

        Public Sub AppendCode() Dim cm As Object Set cm = Application.VBE.VBProjects(1).VBComponents("GeneratedLogic").CodeModule

            cm.InsertLines cm.CountOfLines + 1, _
        "Public Sub NewProc()" & vbCrLf & _
        "    MsgBox ""Dynamically added""" & vbCrLf & _
        "End Sub"
        End Sub
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        • mschuster91 3 days ago

          I've written my fair share of evil shit in VBA.

          But... what is effectively eval() just in VB? Yikes.

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          • moron4hire 3 days ago

            For the people who would be using this, they would almost never even have other people's code, say nothing of whether it's untrusted.

          • n013 2 days ago

            Honestly, ASF is literally sandboxed. Objects cannot be injected in the runtime. Also, VBA Expressions is intentionally limited to receive and return VBA strings. So, the system is safe for execute code from (almost) anyone.

      • n013 2 days ago

        You can inspect the AST in order to debug your code. For syntax highlighting, use tools like Notepad++ (ASF shares most of the syntax with Javascript). Each piece of code is commented, no obscure machine code.

  • fibers 3 days ago

    This looks so useful.