type of entry.
if dlisp_bracket, child != NULL.
if dlisp_cdata, name != NULL
dlisp_cdata
- Constant data
dlisp_bracket
- bracket
dlisp_quotedtext
- quoted text '()
dlisp_stringconstant
- string constant "text"
dlisp_sharp_vector_constant
- sharp vector constant (xx xxx)
dlisp_quasiquote
- quasi-quote `
dlisp_commaat
- ,@()
dlisp_comma
- ,()
dlisp_error
- Error content, this should not exist