Variable assignment

variables a, b, c and d all need to be set to 'foo'.

Is there a 开发者_如何学编程way to accomplish this in one swooping assignment? Like:

a, b, c, d = 'foo'

Ref this

Best way to do it as follow as you need common value to all your variables

a= b= c = d = 'foo'

for different value you can do

a, b, c, d = 'foo1', 'foo2', 'foo3', 'foo4'

I believe Ruby supports the normal type of chained assignment, like:

a = b = c = d = 'foo'

a = b = c = d = 'foo'

is surely the correct way to do it... If you want a bit a freaky way:

a,b,c,d = %w{foo}*4

(%w{foo} returns a string array containing foo, *4 multiplies this array so you get an array containing 4 times the string foo and you can assign an array to multiple comma-separated variable names)

This seems to be safest way:

a, b, c, d = 4.times.map{'foo'}

This one is similar and is a wee bit shorter:

a, b, c, d = (1..4).map{'foo'}

It may be longer than using an array multiplier or chained assignment, but this way you'll actually get different objects, rather than different references to the same object.

Verification code:

[a,b,c,d].map(&:object_id)

If the object_ids are the same, your variables are referring to the same object, and mutator methods (e.g. sub!) will affect what all 4 variables see. If they're different, you can mutate one without affecting the others.