diff options
Diffstat (limited to 'struct.c')
-rw-r--r-- | struct.c | 47 |
1 files changed, 31 insertions, 16 deletions
@@ -524,8 +524,7 @@ rb_struct_define_under(VALUE outer, const char *name, ...) * * - May be anonymous, or may have the name given by +class_name+. * - May have members as given by +member_names+. - * - May have initialization via ordinary arguments (unless - * <tt>keyword_init: true</tt> is given), or via keyword arguments + * - May have initialization via ordinary arguments, or via keyword arguments * * The new subclass has its own method <tt>::new</tt>; thus: * @@ -594,6 +593,12 @@ rb_struct_define_under(VALUE outer, const char *name, ...) * Foo.new(0, 1) # => #<struct Struct::Foo foo=0, bar=1> * Foo.new(0, 1, 2) # Raises ArgumentError: struct size differs * + * # Initialization with keyword arguments: + * Foo.new(foo: 0) # => #<struct Struct::Foo foo=0, bar=nil> + * Foo.new(foo: 0, bar: 1) # => #<struct Struct::Foo foo=0, bar=1> + * Foo.new(foo: 0, bar: 1, baz: 2) + * # Raises ArgumentError: unknown keywords: baz + * * \Method <tt>::[]</tt> is an alias for method <tt>::new</tt>. * * - \Method <tt>:inspect</tt> returns a string representation of the subclass: @@ -608,20 +613,30 @@ rb_struct_define_under(VALUE outer, const char *name, ...) * <b>Keyword Argument</b> * * By default, the arguments for initializing an instance of the new subclass - * are ordinary arguments (not keyword arguments). - * With optional keyword argument <tt>keyword_init: true</tt>, - * the new subclass must be initialized with keyword arguments: - * - * # Without keyword_init: true. - * Foo = Struct.new('Foo', :foo, :bar) - * Foo # => Struct::Foo - * Foo.new(0, 1) # => #<struct Struct::Foo foo=0, bar=1> - * # With keyword_init: true. - * Bar = Struct.new(:foo, :bar, keyword_init: true) - * Bar # => # => Bar(keyword_init: true) - * Bar.new(bar: 1, foo: 0) # => #<struct Bar foo=0, bar=1> - * Bar.new(0, 1) # Raises ArgumentError: wrong number of arguments - * + * can be both positional and keyword arguments. + * + * Optional keyword argument <tt>keyword_init:</tt> allows to force only one + * type of arguments to be accepted: + * + * KeywordsOnly = Struct.new(:foo, :bar, keyword_init: true) + * KeywordsOnly.new(bar: 1, foo: 0) + * # => #<struct KeywordsOnly foo=0, bar=1> + * KeywordsOnly.new(0, 1) + * # Raises ArgumentError: wrong number of arguments + * + * PositionalOnly = Struct.new(:foo, :bar, keyword_init: false) + * PositionalOnly.new(0, 1) + * # => #<struct PositionalOnly foo=0, bar=1> + * PositionalOnly.new(bar: 1, foo: 0) + * # => #<struct PositionalOnly foo={:foo=>1, :bar=>2}, bar=nil> + * # Note that no error is raised, but arguments treated as one hash value + * + * # Same as not providing keyword_init: + * Any = Struct.new(:foo, :bar, keyword_init: nil) + * Any.new(foo: 1, bar: 2) + * # => #<struct Any foo=1, bar=2> + * Any.new(1, 2) + * # => #<struct Any foo=1, bar=2> */ static VALUE |