A name is a sequence of expandables, separated by spaces, that represents a segment in a declaration.

Pane -> {                           // Name with one expandable:
    {"Pane"}                            // Single word
}

Left Pane -> {                      // Name with two expandables:
    {"Left"},                           // Single word +
    {"Pane"}                            // Single word
}

(Left,Right) Pane -> {              // Name with two expandables:
    {"Left","Right"},                   // Expansion +
    {"Pane"}                            // Single word
}

(Top,Bottom) (Left,Right) Pane -> { // Name with three expandables:
    {"Top","Bottom"},                   // Expansion +
    {"Left","Right"},                   // Expansion +
    {"Pane"}                            // Single word
}