diff options
| -rw-r--r-- | ffi.c | 15 | ||||
| -rw-r--r-- | ffi.h | 2 | ||||
| -rw-r--r-- | txr.1 | 21 |
3 files changed, 33 insertions, 5 deletions
@@ -5270,11 +5270,20 @@ mem_t *union_get_ptr(val uni) return us->data; } -val make_union(val type) +val make_union(val type, val init, val memb) { + val self = lit("make-union"); struct txr_ffi_type *tft = ffi_type_struct_checked(type); mem_t *data = chk_calloc(1, tft->size); - return make_union_common(data, tft); + val uni = make_union_common(data, tft); + if (!missingp(init)) { + if (tft->nelem == 0) + uw_throwf(error_s, lit("~a: ~s cannot be initialized: no members"), + self, type, nao); + memb = default_arg(memb, tft->memb[0].mname); + union_put(uni, memb, init); + } + return uni; } val union_members(val uni) @@ -5455,7 +5464,7 @@ void ffi_init(void) reg_fun(intern(lit("num-carray"), user_package), func_n1(num_carray)); reg_fun(intern(lit("put-carray"), user_package), func_n3o(put_carray, 1)); reg_fun(intern(lit("fill-carray"), user_package), func_n3o(fill_carray, 1)); - reg_fun(intern(lit("make-union"), user_package), func_n1(make_union)); + reg_fun(intern(lit("make-union"), user_package), func_n3o(make_union, 1)); reg_fun(intern(lit("union-members"), user_package), func_n1(union_members)); reg_fun(intern(lit("union-get"), user_package), func_n2(union_get)); reg_fun(intern(lit("union-put"), user_package), func_n3(union_put)); @@ -122,7 +122,7 @@ val num_carray(val carray); val put_carray(val carray, val offs, val stream); val fill_carray(val carray, val offs, val stream); mem_t *union_get_ptr(val uni); -val make_union(val type); +val make_union(val type, val init, val memb); val union_members(val uni); val union_get(val uni, val memb); val union_put(val uni, val memb, val newval); @@ -56749,7 +56749,7 @@ following equivalence holds: .coNP Function @ make-union .synb -.mets (make-union << type ) +.mets (make-union < type >> [ initval <> [ member ]]) .syne .desc The @@ -56766,6 +56766,25 @@ The object provides storage for the foreign representation of .codn type , and that storage is initialized to all zero bytes. +Additionally, if +.meta initval +is specified, but +.meta member +is not, then +.meta initval +is stored into the union's via the first member, as if by +.codn union-put . +If the union type has no members, an error exception is thrown. + +If both +.meta initval +and +.meta member +are specified, then +.meta initval +is stored into the union using the specified member, as if by +.codn union-put . + .coNP Function @ union-members .synb .mets (union-members << union ) |