Stand Alone Graphix Applications

As we saw in the overview, using the graphix-shell crate you can build a stand alone Graphix application using rust. With those basics out of the way, in this section we'll see,

• linking multiple Graphix files into a module tree
• integrating rust built-ins
• building a custom repl with rust built-ins added

Module Trees, VFS resolver

In order to split a stand alone Graphix application up into mutiple files and modules and link it all into a single rust binary you can use a kind of module resolver called the VFS. This is pretty much exactly what it sounds like. Here is an example from the TUI library that is built into the shell by default.

#![allow(unused)]
fn main() {
fn tui_mods() -> ModuleResolver {
    ModuleResolver::VFS(HashMap::from_iter([
        (Path::from("/tui"), literal!(include_str!("tui/mod.gx"))),
        (Path::from("/tui/input_handler"), literal!(include_str!("tui/input_handler.gx"))),
        (Path::from("/tui/text"), literal!(include_str!("tui/text.gx"))),
        (Path::from("/tui/paragraph"), literal!(include_str!("tui/paragraph.gx"))),
        (Path::from("/tui/block"), literal!(include_str!("tui/block.gx"))),
        (Path::from("/tui/scrollbar"), literal!(include_str!("tui/scrollbar.gx"))),
        (Path::from("/tui/layout"), literal!(include_str!("tui/layout.gx"))),
        (Path::from("/tui/tabs"), literal!(include_str!("tui/tabs.gx"))),
        (Path::from("/tui/barchart"), literal!(include_str!("tui/barchart.gx"))),
        (Path::from("/tui/chart"), literal!(include_str!("tui/chart.gx"))),
        (Path::from("/tui/sparkline"), literal!(include_str!("tui/sparkline.gx"))),
        (Path::from("/tui/line_gauge"), literal!(include_str!("tui/line_gauge.gx"))),
        (Path::from("/tui/gauge"), literal!(include_str!("tui/gauge.gx"))),
        (Path::from("/tui/list"), literal!(include_str!("tui/list.gx"))),
        (Path::from("/tui/table"), literal!(include_str!("tui/table.gx"))),
        (Path::from("/tui/calendar"), literal!(include_str!("tui/calendar.gx"))),
        (Path::from("/tui/canvas"), literal!(include_str!("tui/canvas.gx"))),
        (Path::from("/tui/browser"), literal!(include_str!("tui/browser.gx"))),
    ]))
}
}

And then when you build the shell, you can specify this ModuleResolver, and your toplevel program can simply use these modules as if they were files on disk.

#![allow(unused)]
fn main() {
ShellBuilder::<NoExt>::default()
    .module_resolvers(vec![tui_mods()])
    .mode(Mode::Static(literal!(include_str!("main.gx"))))
    .publisher(publisher)
    .subscriber(subscriber)
    .no_init(true)
    .build()?
    .run()
    .await
}

You can have as many module resolvers as you like, when loading modules they are checked in order, so earlier ones shadow later ones.

Custom Builtins

To use custom builtins with the shell you must provide a register function

#![allow(unused)]
fn main() {
fn register(ctx: &mut ExecCtx<NoExt>) -> Result<ArcStr> {
    BuiltIn0::register(ctx)?;
    BuiltIn1::register(ctx)?;
    Ok(literal!("builtins.gx"))
}

ShellBuilder::<NoExt>::default()
    .register(Arc::new(|ctx| register(ctx)))
    .module_resolvers(vec![tui_mods()])
    .mode(Mode::Static(literal!(include_str!("main.gx"))))
    .publisher(publisher)
    .subscriber(subscriber)
    .no_init(true)
    .build()?
    .run()
    .await
}

See Implementing Builtins for details on actually implementing builtins.

Custom REPL

You can build a REPL with custom additional Graphix code, or custom builtins, when you build your shell, just change the mode to Mode::Repl. Then you'll get a custom REPL with your desired builtins and pre loaded modules already present.