HB_AAT_LAYOUT_NO_SELECTOR_INDEX

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
extern (C) @nogc nothrow
static if(hbSupport >= HBSupport.v2_6_3)
enum HB_AAT_LAYOUT_NO_SELECTOR_INDEX = 0xFFFFu;

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