A TUI framework for SWI-Prolog, inspired by TEA (The Elm Architecture). Components are defined via the multifile hooks alias_drawable/2 and at_event_is/3.

This module gives the event loop and the core drawables. Ready-made, styled components are opt-in: load library(tui/components).

author

- Mark Bolusmjak

See also

- app/4

 alias_drawable(+DrawableTerm, -ExpandedDrawable) is semidet[multifile]

Multifile hook. Define custom drawable components by mapping a term to its drawable expansion. During rendering the alias is pushed onto the component stack so that at_event_is/3 can intercept events.

See also

- at_event_is/3

 at_event_is(+AliasOrStack, +PositionedEvent, -RewrittenEvent) is nondet[multifile]

Multifile hook. Rewrite an event as seen by a component on the alias stack. PositionedEvent is X-Y-RawEvent, X-Y being where the event happened, relative to the component's origin (absolute for [], the bottom of the stack; with no cursor, [] sees RawEvent alone). Called during event bubbling: each solution replaces the event, and bubbles on from the same component; with none, bubbling continues to the next stack entry. Every event the raw event becomes reaches update, in order.

A cursor movement bubbles as moved(Direction) from where the cursor was, and, for an arrow key no component claimed, as arrived(Direction) where it lands. The cursor moves regardless; what they are rewritten to is handled with the cursor moved. A mouse event bubbles where it happened (see app/5).

Besides events for update, a component may produce a direction, which moves the cursor one cell, or cursor_by(DX-DY), which moves it by an offset; e.g. to keep the cursor after an edit, or, answering arrived(Direction), on a cell where it belongs. noop takes the event to do nothing: it bubbles no further, and update never sees it.

See also

- stack_event_is/3

Undocumented predicates

The following predicates are exported, but not or incorrectly documented.

 direction(Arg1)

 limits_direction_from_to(Arg1, Arg2, Arg3, Arg4)

 drawable(Arg1, Arg2, Arg3, Arg4, Arg5, Arg6, Arg7)

 drawable_raw(Arg1, Arg2)

 stack_event_is(Arg1, Arg2, Arg3)

 app(Arg1, Arg2, Arg3, Arg4)

 app(Arg1, Arg2, Arg3, Arg4, Arg5)

 port_send(Arg1, Arg2)