1 /* Native functions for introspection operations. 2 3 Copyright (C) 2016, 2017 Paul Boddie <paul@boddie.org.uk> 4 5 This program is free software; you can redistribute it and/or modify it under 6 the terms of the GNU General Public License as published by the Free Software 7 Foundation; either version 3 of the License, or (at your option) any later 8 version. 9 10 This program is distributed in the hope that it will be useful, but WITHOUT 11 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 12 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 13 details. 14 15 You should have received a copy of the GNU General Public License along with 16 this program. If not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "types.h" 20 #include "exceptions.h" 21 #include "ops.h" 22 #include "progconsts.h" 23 #include "progops.h" 24 #include "progtypes.h" 25 #include "main.h" 26 27 /* Introspection. */ 28 29 __attr __fn_native_introspection_object_getattr(__attr __args[]) 30 { 31 __attr * const obj = &__args[1]; 32 __attr * const name = &__args[2]; 33 __attr * const _default = &__args[3]; 34 /* name.__data__ interpreted as string */ 35 __attr key = __load_via_object(name->value, __pos___key__); 36 __attr out; 37 38 if ((key.code == 0) && (key.pos == 0)) 39 return *_default; 40 41 /* Attempt to get the attribute from the object. */ 42 43 out = __check_and_load_via_object_null(obj->value, key.pos, key.code); 44 if (out.value == 0) 45 { 46 /* Inspect the object's class if this failed. */ 47 48 out = __check_and_load_via_class(obj->value, key.pos, key.code); 49 if (out.value == 0) 50 return *_default; 51 52 /* Update the context to the object if it is a method. */ 53 54 return __update_context(obj->value, out); 55 } 56 57 return out; 58 } 59 60 static int __issubclass(__ref obj, __attr cls) 61 { 62 return (__HASATTR(obj, __TYPEPOS(cls.value), __TYPECODE(cls.value))); 63 } 64 65 __attr __fn_native_introspection_isinstance(__attr __args[]) 66 { 67 __attr * const obj = &__args[1]; 68 __attr * const cls = &__args[2]; 69 70 /* cls must be a class. */ 71 if (__is_instance(obj->value) && __issubclass(__get_class(obj->value), *cls)) 72 return __builtins___boolean_True; 73 else 74 return __builtins___boolean_False; 75 } 76 77 __attr __fn_native_introspection_issubclass(__attr __args[]) 78 { 79 __attr * const obj = &__args[1]; 80 __attr * const cls = &__args[2]; 81 82 /* obj and cls must be classes. */ 83 if (__issubclass(obj->value, *cls)) 84 return __builtins___boolean_True; 85 else 86 return __builtins___boolean_False; 87 } 88 89 /* Module initialisation. */ 90 91 void __main_native_introspection() 92 { 93 }