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[ci skip] Rejigger the dublicable? wording a bit.

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Kasper Timm Hansen 2016-12-29 20:20:34 +01:00
parent 80ddb7ee2e
commit f2f4fecdf4
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21
guides/source/active_support_core_extensions.md
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@ -135,10 +135,10 @@ NOTE: Defined in `active_support/core_ext/object/blank.rb`.
### `duplicable?`
In Ruby 2.4 most objects can be duplicated throuh `dup` or `clone`, except
method objects and certain numbers. Ruby 2.2 and 2.3 can't duplicate `nil`,
`false`, `true`, and symbols, as well as instances of `Float`, `Fixnum`
and `Bignum`.
In Ruby 2.4 most objects can be duplicated via `dup` or `clone` except
methods and certain numbers. Though Ruby 2.2 and 2.3 can't duplicate `nil`,
`false`, `true`, and symbols as well as instances `Float`, `Fixnum`,
and `Bignum` instances.
```ruby
"foo".dup # => "foo"
@ -147,8 +147,7 @@ and `Bignum`.
Complex(0).dup # => TypeError: can't copy Complex
```
Active Support provides `duplicable?` to programmatically query an object about
this property:
Active Support provides `duplicable?` to query an object about this:
```ruby
"foo".duplicable? # => true
@ -158,10 +157,11 @@ Complex(1).duplicable? # => false
1.method(:+).duplicable? # => false
```
`duplicable?` returns the correct result for the version of Ruby used.
`duplicable?` matches Ruby's `dup` according to the Ruby version.
So in 2.4:
```ruby
# version 2.4
nil.dup # => nil
:my_symbol.dup # => :my_symbol
1.dup # => 1
@ -169,8 +169,11 @@ nil.dup # => nil
nil.duplicable? # => true
:my_symbol.duplicable? # => true
1.duplicable? # => true
```
# version 2.2 and 2.3
Whereas in 2.2 and 2.3:
```ruby
nil.dup # => TypeError: can't dup NilClass
:my_symbol.dup # => TypeError: can't dup Symbol
1.dup # => TypeError: can't dup Fixnum