Ppx_solidtypeLowers each JSX element MLX parses -- an application marked [@JSX] -- into one call of Solidtype.Jsx, the marker the Vite plugin rewrites into Solid's JSX, and writes a component from let%component.
An element <div class_="x" /> becomes Jsx.el "div", and a component <Counter initial=1 /> becomes Jsx.c Counter.component. A literal, a JSX element, a handler (on_ and its event, on_click), a function literal other than fun () -> ... and a name, <Row changed />, are static; anything else is a thunk, so a read outside a thunk does not compile. A function prop that takes no argument is written (fun _ -> ...), since fun () -> ... is a thunk. A string literal, however quoted, is written as a JavaScript string, {js|...|js}, its backslashes doubled, so text that is not ASCII and a backslash reach the page as written; one written {js|...|js} is JavaScript's already, and left as it is.
An element's attribute is annotated with its type from the element's module of Solidtype.Html, Html.Div.class_. Its name is given back its JavaScript spelling by the rule's inverse -- a keyword's trailing underscore dropped, a hyphen after aria_ and data_, aria_label, and a capital after any other underscore, read_only -- or by the tables the generators write of the names the inverse does not give, stroke_width. One of Solid's namespaces wraps the value, never the name: on_click=(Jsx.capture f) is oncapture:click, and Jsx.native, Jsx.prop, Jsx.attr and Jsx.bool name the others.
A data_ attribute's value is a Jsx.data, on an element and on a component alike, and a string literal is written as Jsx.data for it. A component's check takes none of them, as TSX checks no hyphenated attribute of a component: each is passed on as a prop of its JavaScript name, data_hovered as data-hovered.
A component's element also applies Counter.Props.check to its props under if false, so a prop left out or not taken is a compile error, and Melange writes none of it. props=p spreads p without copying it, TSX's {...p}, so no prop is named props. A child is a string literal, an element, or a thunk of Solidtype.Jsx.content; a component's only child may be a function the component calls. A Switch whose only child is a thunk of a match gets a Match per case, a Match.Keyed where the case binds variables, and the match is also checked whole, so a case left out is the compiler's warning.
let%component make ~(text : string) ?(count : int = 0) () = body writes the module's Props -- its type, a getter per prop, make, which builds props as a value, check, and omit, which names props by a variant of their own -- and make and component. In body a value prop is read as a thunk, text (), and a function prop is called, on_pick v, an optional one giving Some of its result or None: each is a live read of Solid's props, so Solid tracks it.
-internal lowers JSX inside solidtype itself, naming its modules without Solidtype..