Indexes

Sometimes you may want to rearrange values in an array or dictionary and detect what has been moved. Teisu.indexes allows you to do this.

Usage

To create an indexes object, call Teisu.indexes and pass in an input molecule and a transformer function.

local indexes = Teisu.indexes

local todos = flec({ "go shopping", "eat food", "head back home" })

local numbered_todos = indexes(todos, function(value, index)
    return `{index()}. {value}`
end)

You can access numbered_todos's contents like a computed:

print(numbered_todos()) --> { "1. go shopping", "2. eat food", "3. head back home" }
print(peek(numbered_todos))

Whenever your input molecule changes, the output will update.

todos({ "eat food", "go shopping", "head back home" })

print(numbered_todos()) --> { "1. eat food", "2. go shopping", "3. head back home" }

If Teisu.cleanup is called, any object passed in as an argument will get cleaned up when a processed key is removed.

Luau code

local numbered_todos = indexes(todos, function(value)
    cleanup(function()
        print("removed a todo!")
    end)

    return `{index()}. {value}`
end)

todos({ "eat food", "head back home" })

print(numbered_todos())

Output

removed a todo!
{ "1. eat food", "2. head back home" }