SEXPREC: R's fundamental data type at C level
In ramiromagno/c3po: From C to R and back again

Description Declaration References See Also

\Sexpr[results=rd, stage=render]{c3po:::badge('typedef-str')}\Sexpr[results=rd, stage=render]{c3po:::badge('USE_RINTERNALS')}

S-expression (SEXP) record (REC) structure, a C structure underlying every R object. Accessible via a pointer of type SEXP. SEXPREC is a variant type, with subtypes for all R’s data structures (see SEXPTYPE for a list of subtypes).

The SEXPREC is composed of two parts (five struct members in total):

Header, SEXPREC_HEADER:
- struct sxpinfo_struct sxpinfo
- struct SEXPREC *attrib
- struct SEXPREC *gengc_next_node
- struct SEXPREC *gengc_prev_node

Node data, u.

typedef struct SEXPREC {
    SEXPREC_HEADER;
    union {
  struct primsxp_struct primsxp;
  struct symsxp_struct symsxp;
  struct listsxp_struct listsxp;
  struct envsxp_struct envsxp;
  struct closxp_struct closxp;
  struct promsxp_struct promsxp;
    } u;
} SEXPREC;