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authorknu <knu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2019-03-11 09:49:14 +0000
committerknu <knu@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>2019-03-11 09:49:14 +0000
commitc2d3b8dfb43e6dbc0b9af3c0f880636ffcc06ca9 (patch)
tree3ddc67451c963d775f07eb9f1092fed7974a58bb /enumerator.c
parent7d9664953ba574b04f6558e80e95a71289275d64 (diff)
downloadruby-c2d3b8dfb43e6dbc0b9af3c0f880636ffcc06ca9.tar.gz
Implement Enumerator::Yielder#to_proc
A Yielder object can now be directly passed to another method as a block argument. ```ruby enum = Enumerator.new { |y| Dir.glob("*.rb") { |file| File.open(file) { |f| f.each_line(&y) } } } ``` git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67211 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'enumerator.c')
-rw-r--r--enumerator.c27
1 files changed, 25 insertions, 2 deletions
diff --git a/enumerator.c b/enumerator.c
index edaeb52da0..5311b47cdb 100644
--- a/enumerator.c
+++ b/enumerator.c
@@ -110,8 +110,8 @@ VALUE rb_cEnumerator;
static VALUE rb_cLazy;
static ID id_rewind, id_new, id_to_enum;
static ID id_next, id_result, id_receiver, id_arguments, id_memo, id_method, id_force;
-static ID id_begin, id_end, id_step, id_exclude_end;
-static VALUE sym_each, sym_cycle;
+static ID id_begin, id_end, id_step, id_exclude_end, id_to_proc;
+static VALUE sym_each, sym_cycle, sym_yield;
#define id_call idCall
#define id_each idEach
@@ -1288,6 +1288,26 @@ yielder_yield_push(VALUE obj, VALUE arg)
return obj;
}
+/*
+ * Returns a Proc object that takes an argument and yields it.
+ *
+ * This method is implemented so that a Yielder object can be directly
+ * passed to another method as a block argument.
+ *
+ * enum = Enumerator.new { |y|
+ * Dir.glob("*.rb") { |file|
+ * File.open(file) { |f| f.each_line(&y) }
+ * }
+ * }
+ */
+static VALUE
+yielder_to_proc(VALUE obj)
+{
+ VALUE method = rb_obj_method(obj, sym_yield);
+
+ return rb_funcall(method, id_to_proc, 0);
+}
+
static VALUE
yielder_yield_i(RB_BLOCK_CALL_FUNC_ARGLIST(obj, memo))
{
@@ -3380,6 +3400,7 @@ InitVM_Enumerator(void)
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_push, 1);
+ rb_define_method(rb_cYielder, "to_proc", yielder_to_proc, 0);
/* Chain */
rb_cEnumChain = rb_define_class_under(rb_cEnumerator, "Chain", rb_cEnumerator);
@@ -3430,8 +3451,10 @@ Init_Enumerator(void)
id_end = rb_intern("end");
id_step = rb_intern("step");
id_exclude_end = rb_intern("exclude_end");
+ id_to_proc = rb_intern("to_proc");
sym_each = ID2SYM(id_each);
sym_cycle = ID2SYM(rb_intern("cycle"));
+ sym_yield = ID2SYM(rb_intern("yield"));
InitVM(Enumerator);
}