Glossary

• App: a Lua program running on the workstation, from a script or a package. Every app has a place in the tree of apps that started each other (How your app runs).
• Asset pack: a package of files and no code, such as a theme, a book or a dataset (Packages and identity).
• Base layer: where the root app stacks: under every window it manages, while its own popovers and menus stack above them (Input, focus and Back).
• Bootstrap: the root app; datumhue.app.bootstrap returns it (Grants flow down).
• Callback: a function your app hands to DatumHue to call later, such as a timer or a button's on_click (How your app runs).
• Cancel request: the one Back that Escape, gamepad B, the mouse's back button and a browser's or phone's Back all make. The innermost part of the UI that can take it does (Input, focus and Back).
• Capability: a handle that grants access to one resource, such as a folder or a file. Not the same as a permission (Permissions and capabilities).
• Content area: the part of an app's window where its UI lives; what you build on datumhue.ui.root goes there (The app window).
• Density: how large an app's controls, text and spacing are: standard for a mouse, larger for touch (Theme and density).
• Handle: a typed value that stands for something DatumHue keeps for your app: a canvas, a widget, a file, a save in progress (API conventions).
• HTTP mount: a handle that reaches one web service your deployment offers (Call a web API).
• Library: a package of modules that other packages load with require (Modules and dependencies).
• Manifest: a package's package.kdl, which names it, versions it and says what it needs (Manifest reference).
• Member: a package a workspace lists in its workspace.kdl (Work on several packages together).
• Module: a .lua file under a package's lib/, loaded with require (Modules and dependencies).
• Native plugin: a library of native code that adds namespaces and handle classes to the datumhue.* API (Native plugins).
• Package: a folder with a package.kdl manifest and a fixed layout; what you run, share and depend on (Packages and identity).
• Permission: a named grant, such as screenshot, that opens one area of the API. Permissions pass down the tree of apps and only narrow (Permissions and capabilities).
• Root app: the first app a launch starts, usually a window manager. It holds every permission (Grants flow down).
• Root container: an app's window, as a window manager places and sizes it (The app window).
• Service app: an app with no window, which ends once nothing is registered (How your app runs).
• Session: an id every launch has, telling it apart from other launches running at the same time (Sessions).
• Suspending call: a call that pauses your code, and the rest of your app, until its result is ready (Waiting).
• UI app: an app with a window (How your app runs).
• UI px: the unit your UI is measured in: the window's logical pixels divided by the zoom (Coordinates and units).
• Window manager: the app that starts and arranges other apps. It is an ordinary app, and usually the root app (Write a window manager or launcher).
• Workspace: a folder of packages you develop together, listed in a workspace.kdl (Work on several packages together).
• Zoom: the comfort setting the person using the workstation picks, a multiplier on every UI px (Fit any window size).

Reference used on this page: datumhue.app.bootstrap datumhue.ui.root