Arturo Programming Language

Arturo is primarily written in Nim, with C/C++ used for external libraries and wrappers. The project is organized into several key directories:

• src/: The main source code.
• src/vm/: The Virtual Machine core, including:
  • parse.nim: Lexer/parser (input to parse tree).
  • eval.nim: Evaluator (parse tree to bytecode).
  • exec.nim: Execution engine (bytecode loop).
  • stack.nim: Stack manipulation.
  • value.nim: The core Value object and arithmetic/printing logic.
  • bytecode.nim: Bytecode definitions.
  • env.nim: VM environment handling.
• src/library/: The Arturo standard library.
• src/system/: Components written in Arturo (REPL, packager, etc.).
• src/helpers/: Shared utility methods.
• src/extras/: 3rd party open-source code.
• examples/: Working Arturo code examples.
• tests/: Unit tests.
• bin/: Destination for the compiled binary.

Arturo's library reference and the info function are automatically generated from the source code of the built-in modules located in src/library. Each built-in function is defined using a builtin macro that includes metadata such as description, args, returns, and example. When you add or modify a builtin definition in a library module, the documentation is updated automatically.

    builtin "darken",
        alias       = unaliased, 
        rule        = PrefixPrecedence,
        description = "darken color by given percentage (0.0-1.0)",
        args        = {
            "color"     : {ValueKind.Color},
            "percent"   : {Floating}
        },
        attrs       = NoAttrs,
        returns     = {ValueKind.Color},
        example     = """
            darken #red 0.2         ; => #CC0000
            darken #red 0.5         ; => #7F0000
            darken #9944CC 0.3      ; => #6B308F
        """:
            ##########################################################
            if x.kind == Literal:
                SetInPlace(newColor(alterColorValue(InPlace.l, y.f * (-1))))
            else:
                push newColor(alterColorValue(x.l, y.f * (-1)))

If you need to pull the latest source files from the webview/webview parent repository into Arturo, follow these manual steps to ensure compatibility across Windows and Unix platforms without converting the Nim project to C++.

Note: This process involves splitting the parent files into specific Arturo files (webview-windows.h, webview.h, and webview-unix.cc) and updating the Nim bindings.

1. Update Header and Implementation Files

Let P denote the parent files (webview/webview) and A denote Arturo's files.

• For Windows (A:webview-windows.h):

  • Copy the entire contents of P:webview.h into A:webview-windows.h.

• For the Common Header (A:webview.h):

  • Locate the section in P:webview.h starting immediately after #define WEBVIEW_H (but before #ifndef WEBVIEW_API) and ending just before #ifndef WEBVIEW_HEADER.
  • Copy this section into A:webview.h.
  • Important: Do not include the #ifndef WEBVIEW_HEADER line. Note that a trailing #endif will be missing; you must ensure the header is valid.

• For Unix (A:webview-unix.cc):

  • Locate the section in P:webview.h starting from #ifndef WEBVIEW_API (including preceding comments) until the final #endif /* __cplusplus */.
  • Copy this into A:webview-unix.cc.
  • Important: Remove the #ifndef WEBVIEW_HEADER statement and its corresponding #endif from this section.

2. Update Nim Bindings

After updating the C/C++ files, you must ensure the Nim interface matches the new source:

• Verify that the main function signatures have not changed.
• If signatures have changed or new functions have been added to the parent repository, add the corresponding definitions to extras/webview.nim.