Render a list with positional updates

Like Each(), but when list values change without a length change, each slot's reactive value is updated in place rather than recreating the DOM. When the list grows, new slots are appended; when it shrinks, trailing slots are destroyed.

Usage

Index(items, fn)

Arguments

items

A reactive expression that returns a list.

fn

A function of (item) or (item, index) where item is a shiny::reactiveVal() for the item at that position and index is its fixed position (plain integer). Should return a tag tree.

Value

A nacre control-flow node.