FIRST_WORD_IN_DOCUMENT = "first-word-in-document"
FIRST_WORD_IN_SEGMENT = "first-word-in-segment"
FIRST_WORD_IN_LINE = "first-word-in-line"

LAST_WORD_IN_DOCUMENT = "last-word-in-document"
LAST_WORD_IN_SEGMENT = "last-word-in-segment"
LAST_WORD_IN_LINE = "last-word-in-line"

FIRST_LINE_IN_DOCUMENT = "first-line-in-document"
FIRST_LINE_IN_SEGMENT = "first-line-in-segment"
LAST_LINE_IN_DOCUMENT = "last-line-in-document"
LAST_LINE_IN_SEGMENT = "last-line-in-segment"

FIRST_SEGMENT_IN_DOCUMENT = "first-segment-in-document"
LAST_SEGMENT_IN_DOCUMENT = "last-segment-in-document"