pike.git/ src/ builtin_functions.c

2002-05-11

2002-05-11 21:08:00 by Martin Stjernholm <mast@lysator.liu.se>

• 0ee38f3118251314d245ecdb85dd7835c2679070 (95 lines) (+86/-9) ^{[ Show | Annotate ]}
  Branch: 7.9

Cleaned up and fixed some bugs in the lookup of magic program identifiers
like this_program and ::`->. It's now possible to use e.g.
global::this_program. Added an optional level argument to this_object().

Added a magic identifier "this" that can be used instead of this_object().
Like this_program, it only exists when there's no other identifier with that
name. The object of a surrounding class can be adressed with Foo::this.

Rev: src/builtin_functions.c:1.428
Rev: src/interpret_functions.h:1.103
Rev: src/language.yacc:1.283
Rev: src/program.c:1.430
Rev: src/program.h:1.160

5:   \*/   /**/   #include "global.h" - RCSID("$Id: builtin_functions.c,v 1.427 2002/05/10 23:38:10 nilsson Exp $"); + RCSID("$Id: builtin_functions.c,v 1.428 2002/05/11 21:07:59 mast Exp $");   #include "interpret.h"   #include "svalue.h"   #include "pike_macros.h"
1847:    Pike_sp++;   }    - /*! @decl object this_object(); + /*! @decl object this_object(void|int level);    *!    *! Returns the object we are currently evaluating in. -  +  *! +  *! @[level] might be used to access the object of a surrounding +  *! class: The object at level 0 is the current object, the object +  *! at level 1 is the one belonging to the class surrounding the +  *! current class, and so on.    */   void f_this_object(INT32 args)   { -  +  int level; +  if (args) { +  if (Pike_sp[-args].type != T_INT || Pike_sp[-args].u.integer < 0) +  SIMPLE_BAD_ARG_ERROR ("this_object", 1, "a non-negative integer"); +  level = Pike_sp[-args].u.integer; +  } +  else +  level = 0; +     pop_n_elems(args);    if(Pike_fp)    { -  ref_push_object(Pike_fp->current_object); +  struct object *o = Pike_fp->current_object; +  for (; level > 0; level--) { +  struct program *p = o->prog; +  if (!p) +  Pike_error ("Cannot get the parent object of a destructed object.\n"); +  if (!(p->flags & PROGRAM_USES_PARENT)) +  /* FIXME: Ought to write out the object here. */ +  Pike_error ("Object lacks parent reference.\n"); +  o = PARENT_INFO(o)->parent; +  } +  ref_push_object(o);    }else{ -  +  /* Shouldn't this generate an error? /mast */    push_int(0);    }   }    - node *fix_this_object_type(node *n) + static node *optimize_this_object(node *n)   { -  +  int id; +  +  if (CDR (n)) { +  struct program_state *state = Pike_compiler; +  if (CDR (n)->token != F_CONSTANT) { +  /* Not a constant expression. Make sure there are parent +  * pointers all the way. */ +  int i; +  for (i = 0; i < compilation_depth; i++, state = state->previous) +  state->new_program->flags |= PROGRAM_USES_PARENT | PROGRAM_NEEDS_PARENT; +  return NULL; +  } +  else { +  int level; + #ifdef PIKE_DEBUG +  if (CDR (n)->u.sval.type != T_INT || CDR (n)->u.sval.u.integer < 0) +  fatal ("The type check for this_object() failed.\n"); + #endif +  level = CDR (n)->u.sval.u.integer; +  if (level > compilation_depth) { +  my_yyerror ("There is no surrounding class %d levels out.", level); +  return NULL; +  } +  for (; level > 0; level--, state = state->previous) +  state->new_program->flags |= PROGRAM_USES_PARENT | PROGRAM_NEEDS_PARENT; +  id = state->new_program->id; +  } +  } +  else id = Pike_compiler->new_program->id; +     free_type(n->type);    type_stack_mark();       /* We are rather sure that we contain ourselves... */    /* push_object_type(1, Pike_compiler->new_program->id); */    /* But it did not work yet, so... */ -  push_object_type(0, Pike_compiler->new_program->id); +  push_object_type(0, id);    n->type = pop_unfinished_type();    if (n->parent) {    n->parent->node_info |= OPT_TYPE_NOT_FIXED;
1880:      static int generate_this_object(node *n)   { -  emit0(F_THIS_OBJECT); +  int level; +  +  if (CDR (n)) { +  struct program_state *state = Pike_compiler; +  if (CDR (n)->token != F_CONSTANT) +  /* Not a constant expression. Make a call to f_this_object. */ +  return 0; +  else { + #ifdef PIKE_DEBUG +  if (CDR (n)->u.sval.type != T_INT || CDR (n)->u.sval.u.integer < 0) +  fatal ("The type check for this_object() failed.\n"); + #endif +  level = CDR (n)->u.sval.u.integer; + #ifdef PIKE_DEBUG +  if (level > compilation_depth) +  fatal ("this_object level too high. " +  "Expected this to be caught by optimize_this_object.\n"); + #endif +  } +  } +  else level = 0; +  +  emit1(F_THIS_OBJECT, level);    return 1;   }   
7695:   /* function(mixed:int) */    ADD_EFUN("stringp", f_stringp,tFunc(tMix,tInt),0);    - /* function(:object) */ -  ADD_EFUN2("this_object", f_this_object,tFunc(tNone,tObj), -  OPT_EXTERNAL_DEPEND, fix_this_object_type, generate_this_object); +  ADD_EFUN2("this_object", f_this_object,tFunc(tOr(tVoid,tIntPos),tObj), +  OPT_EXTERNAL_DEPEND, optimize_this_object, generate_this_object);      /* function(mixed:void) */    ADD_EFUN("throw",f_throw,tFunc(tMix,tVoid),OPT_SIDE_EFFECT);