* enumerator.c (enumerator_initialize): Add an ability to generate

an enumerator from a block. [ruby-dev:35903]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@20631 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
This commit is contained in:
knu 2008-12-11 10:39:31 +00:00
parent 8707c67dbf
commit f6895becb9
3 changed files with 317 additions and 13 deletions

View file

@ -1,3 +1,8 @@
Thu Dec 11 19:33:10 2008 Akinori MUSHA <knu@iDaemons.org>
* enumerator.c (enumerator_initialize): Add an ability to generate
an enumerator from a block. [ruby-dev:35903]
Thu Dec 11 19:08:38 2008 Akinori MUSHA <knu@iDaemons.org>
* enumerator.c (enum_each_with_object): Add

10
NEWS
View file

@ -27,12 +27,14 @@ with all sufficient information, see the ChangeLog file.
New method with which replaces #choice.
* Enumerable#each_with_object
New method.
* Enumerator#with_object
New method.
New methods.
* Enumerator.new { |y| ... }
Now can generate an enumerator from a block that defines
enumeration instead of an enumerable object.
* Hash#default_proc=

View file

@ -33,7 +33,25 @@ struct enumerator {
rb_block_call_func *iter;
};
static VALUE rb_cGenerator, rb_cYielder;
struct generator {
VALUE proc;
};
struct yielder {
VALUE proc;
};
static VALUE generator_allocate _((VALUE klass));
static VALUE generator_init _((VALUE obj, VALUE proc));
/*
* Enumerator
*/
static void enumerator_mark _((void *));
static void
enumerator_mark(p)
void *p;
@ -292,12 +310,34 @@ enumerator_init(enum_obj, obj, meth, argc, argv)
/*
* call-seq:
* Enumerator.new(obj, method = :each, *args)
* Enumerator.new { |y| ... }
*
* Creates a new Enumerator object, which is to be used as an
* Enumerable object using the given object's given method with the
* given arguments.
* Enumerable object iterating in a given way.
*
* Use of this method is discouraged. Use Kernel#enum_for() instead.
* In the first form, a generated Enumerator iterates over the given
* object using the given method with the given arguments passed.
* Use of this form is discouraged. Use Kernel#enum_for(), alias
* to_enum, instead.
*
* e = Enumerator.new(ObjectSpace, :each_object)
* #-> ObjectSpace.enum_for(:each_object)
*
* e.select { |obj| obj.is_a?(Class) } #=> array of all classes
*
* In the second form, iteration is defined by the given block, in
* which a "yielder" object given as block parameter can be used to
* yield a value by calling the +yield+ method, alias +<<+.
*
* fib = Enumerator.new { |y|
* a = b = 1
* loop {
* y << a
* a, b = b, a + b
* }
* }
*
* p fib.take(10) #=> [1, 1, 2, 3, 5, 8, 13, 21, 34, 55]
*/
static VALUE
enumerator_initialize(argc, argv, obj)
@ -307,13 +347,19 @@ enumerator_initialize(argc, argv, obj)
{
VALUE recv, meth = sym_each;
if (argc == 0)
rb_raise(rb_eArgError, "wrong number of argument (0 for 1)");
if (argc == 0) {
if (!rb_block_given_p())
rb_raise(rb_eArgError, "wrong number of argument (0 for 1+)");
recv = generator_init(generator_allocate(rb_cGenerator), rb_block_proc());
} else {
recv = *argv++;
if (--argc) {
meth = *argv++;
--argc;
}
}
return enumerator_init(obj, recv, meth, argc, argv);
}
@ -490,6 +536,242 @@ enumerator_rewind(obj)
return rb_funcall(obj, rb_intern("rewind"), 0, 0);
}
/*
* Yielder
*/
static void yielder_mark _((void *));
static void
yielder_mark(void *p)
{
struct yielder *ptr = p;
rb_gc_mark(ptr->proc);
}
static struct yielder *
yielder_ptr(VALUE obj)
{
struct yielder *ptr;
Data_Get_Struct(obj, struct yielder, ptr);
if (RDATA(obj)->dmark != yielder_mark) {
rb_raise(rb_eTypeError,
"wrong argument type %s (expected %s)",
rb_obj_classname(obj), rb_class2name(rb_cYielder));
}
if (!ptr || ptr->proc == Qundef) {
rb_raise(rb_eArgError, "uninitialized yielder");
}
return ptr;
}
static VALUE yielder_allocate _((VALUE));
/* :nodoc: */
static VALUE
yielder_allocate(klass)
VALUE klass;
{
struct yielder *ptr;
VALUE obj;
obj = Data_Make_Struct(klass, struct yielder, yielder_mark, -1, ptr);
ptr->proc = Qundef;
return obj;
}
static VALUE
yielder_init(obj, proc)
VALUE obj, proc;
{
struct yielder *ptr;
Data_Get_Struct(obj, struct yielder, ptr);
if (!ptr) {
rb_raise(rb_eArgError, "unallocated yielder");
}
ptr->proc = proc;
return obj;
}
/* :nodoc: */
static VALUE
yielder_initialize(obj)
VALUE obj;
{
rb_need_block();
return yielder_init(obj, rb_block_proc());
}
/* :nodoc: */
static VALUE
yielder_yield(obj, args)
VALUE obj, args;
{
struct yielder *ptr = yielder_ptr(obj);
rb_proc_call(ptr->proc, args);
return obj;
}
static VALUE
yielder_new_i(dummy)
VALUE dummy;
{
return yielder_init(yielder_allocate(rb_cYielder), rb_block_proc());
}
static VALUE
yielder_yield_i(obj, memo)
VALUE obj, memo;
{
return rb_yield(obj);
}
static VALUE
yielder_new()
{
return rb_iterate(yielder_new_i, (VALUE)0, yielder_yield_i, (VALUE)0);
}
/*
* Generator
*/
static void generator_mark _((void *));
static void
generator_mark(p)
void *p;
{
struct generator *ptr = p;
rb_gc_mark(ptr->proc);
}
static struct generator *
generator_ptr(obj)
VALUE obj;
{
struct generator *ptr;
Data_Get_Struct(obj, struct generator, ptr);
if (RDATA(obj)->dmark != generator_mark) {
rb_raise(rb_eTypeError,
"wrong argument type %s (expected %s)",
rb_obj_classname(obj), rb_class2name(rb_cGenerator));
}
if (!ptr || ptr->proc == Qundef) {
rb_raise(rb_eArgError, "uninitialized generator");
}
return ptr;
}
static VALUE generator_allocate _((VALUE));
/* :nodoc: */
static VALUE
generator_allocate(klass)
VALUE klass;
{
struct generator *ptr;
VALUE obj;
obj = Data_Make_Struct(klass, struct generator, generator_mark, -1, ptr);
ptr->proc = Qundef;
return obj;
}
static VALUE
generator_init(obj, proc)
VALUE obj, proc;
{
struct generator *ptr;
Data_Get_Struct(obj, struct generator, ptr);
if (!ptr) {
rb_raise(rb_eArgError, "unallocated generator");
}
ptr->proc = proc;
return obj;
}
VALUE rb_obj_is_proc _((VALUE));
/* :nodoc: */
static VALUE
generator_initialize(argc, argv, obj)
int argc;
VALUE *argv;
VALUE obj;
{
VALUE proc;
if (argc == 0) {
rb_need_block();
proc = rb_block_proc();
} else {
rb_scan_args(argc, argv, "1", &proc);
if (!rb_obj_is_proc(proc))
rb_raise(rb_eTypeError,
"wrong argument type %s (expected Proc)",
rb_obj_classname(proc));
if (rb_block_given_p()) {
rb_warn("given block not used");
}
}
return generator_init(obj, proc);
}
/* :nodoc: */
static VALUE
generator_init_copy(obj, orig)
VALUE obj, orig;
{
struct generator *ptr0, *ptr1;
ptr0 = generator_ptr(orig);
Data_Get_Struct(obj, struct generator, ptr1);
if (!ptr1) {
rb_raise(rb_eArgError, "unallocated generator");
}
ptr1->proc = ptr0->proc;
return obj;
}
/* :nodoc: */
static VALUE
generator_each(obj)
VALUE obj;
{
struct generator *ptr = generator_ptr(obj);
VALUE yielder;
yielder = yielder_new();
rb_proc_call(ptr->proc, rb_ary_new3(1, yielder));
return obj;
}
void
Init_Enumerator()
{
@ -518,6 +800,21 @@ Init_Enumerator()
rb_eStopIteration = rb_define_class("StopIteration", rb_eIndexError);
/* Generator */
rb_cGenerator = rb_define_class_under(rb_cEnumerator, "Generator", rb_cObject);
rb_include_module(rb_cGenerator, rb_mEnumerable);
rb_define_alloc_func(rb_cGenerator, generator_allocate);
rb_define_method(rb_cGenerator, "initialize", generator_initialize, -1);
rb_define_method(rb_cGenerator, "initialize_copy", generator_init_copy, 1);
rb_define_method(rb_cGenerator, "each", generator_each, 0);
/* Yielder */
rb_cYielder = rb_define_class_under(rb_cEnumerator, "Yielder", rb_cObject);
rb_define_alloc_func(rb_cYielder, yielder_allocate);
rb_define_method(rb_cYielder, "initialize", yielder_initialize, 0);
rb_define_method(rb_cYielder, "yield", yielder_yield, -2);
rb_define_method(rb_cYielder, "<<", yielder_yield, -2);
sym_each = ID2SYM(rb_intern("each"));
/* backward compatibility */