//- 💫 DOCS > API > CYTHON > CLASSES > DOC

p
    |  The #[code Doc] object holds an array of
    |  #[+api("cython-structs#tokenc") #[code TokenC]] structs.

+infobox
    |  This section documents the extra C-level attributes and methods that
    |  can't be accessed from Python. For the Python documentation, see
    |  #[+api("doc") #[code Doc]].

+h(3, "doc_attributes") Attributes

+table(["Name", "Type", "Description"])
    +row
        +cell #[code mem]
        +cell #[code cymem.Pool]
        +cell
            |  A memory pool. Allocated memory will be freed once the
            |  #[code Doc] object is garbage collected.

    +row
        +cell #[code vocab]
        +cell #[code Vocab]
        +cell A reference to the shared #[code Vocab] object.

    +row
        +cell #[code c]
        +cell #[code TokenC*]
        +cell
            |  A pointer to a #[+api("cython-structs#tokenc") #[code TokenC]]
            |  struct.

    +row
        +cell #[code length]
        +cell #[code int]
        +cell The number of tokens in the document.

    +row
        +cell #[code max_length]
        +cell #[code int]
        +cell The underlying size of the #[code Doc.c] array.

+h(3, "doc_push_back") Doc.push_back
    +tag method

p
    |  Append a token to the #[code Doc]. The token can be provided as a
    |  #[+api("cython-structs#lexemec") #[code LexemeC]] or
    |  #[+api("cython-structs#tokenc") #[code TokenC]] pointer, using Cython's
    |  #[+a("http://cython.readthedocs.io/en/latest/src/userguide/fusedtypes.html") fused types].

+aside-code("Example").
    from spacy.tokens cimport Doc
    from spacy.vocab cimport Vocab

    doc = Doc(Vocab())
    lexeme = doc.vocab.get(u'hello')
    doc.push_back(lexeme, True)
    assert doc.text == u'hello '

+table(["Name", "Type", "Description"])
    +row
        +cell #[code lex_or_tok]
        +cell #[code LexemeOrToken]
        +cell The word to append to the #[code Doc].

    +row
        +cell #[code has_space]
        +cell #[code bint]
        +cell Whether the word has trailing whitespace.