DQD: the @ operator

The @ operator expresses a character-wise overlap relation. As such, it can only be applied to entities that are character-aligned, for example tokens or segments (unlike gesture annotations of video corpora that, typically, are not character-aligned).

It is a binary operator: it uses the syntax x@y, where x and y are labels referring to entities that should overlap along the character axis. In the particular case where x refers to a parent of the annotation unit referred to by y, for example a Segment-Token relation, the @ operator essentially expresses a containment relation.

x can be of two types. First, it can be the name of an annotation layer in the corpus. For example, the block below means that the adverb token t1 should be part of the segment labeled s

 Segment s
    speaker.name = "Marcel"

 Token@s t1
    upos = "ADV"

Second, it can be the keyword sequence, in which case all the entities declared within the scope of the sequence must be contained within the labeled entity. For example, the block below means that we are looking for a named entity contained in a segment, which itselfs contains the sequence "Monte Rosa":

Segment s

NamedEntity@s ne

sequence@ne seq
    Token
        form = "Monte"
    Token
        form = "Rosa"