One-line assignment: If (condition) variable = value1 else value2

Question

How do I do something like this?

if params[:property] == nil 
 @item.property = true
else 
 @item.property = false

Always forget the proper syntax to write it in one line.

In PHP it would be like this:

@item.property=(params[:property]==nil)true:false

Is it the same in rails?

That's not valid PHP code, is it? That statement looks like this afaik: $item->property = ($something === NULL) ? true : false — Kloar
– Kloar, Commented Dec 8, 2012 at 12:33

m_x · Accepted Answer · 2012-12-08 11:35:00Z

17

use the ternary operator:

@item.property = params[:property] ? true : false

or force a boolean conversion ("not not" operation) :

@item.property = !!params[:property]

note : in ruby, it is a common idiom not to use true booleans, as any object other than false or nil evaluates to true.

answered Dec 8, 2012 at 11:35

m_x

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Comments

Michaël Witrant · Accepted Answer · 2012-12-08 12:30:57Z

0

m_x answer is perfect but you may be interested to know other ways to do it, which may look better in other circumstances:

if params[:property] == nil then @item.property = true else @item.property = false end

or

@item.property = if params[:property] == nil then true else false end

answered Dec 8, 2012 at 12:30

Michaël Witrant

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