Re: [Rails] Rails Syntax Change

[Walter Lee Davis]

On Sep 9, 2012, at 12:10 PM, rails2012 wrote:

> I am a newbie. Looking at some old text vs new. I see some changes:
>
> New: <%= yield(:title) %>
> Old: <%= @title %>
>

Not sure about this one.

> New: "#{base_title} | Home"
> Old: @base_title + "| Home"

The new way creates one fewer String object, and that can only be good for performance and memory usage.

Walter

>
> Can you tell me when they got changed? Are the new syntax now the preferred way? Are they more elegant?
>
> Thanks!
>
>
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[7stud --]

> New: <%= yield(:title) %>
> Old: <%= @title %>

@title is set in a controller, and to separate views from what goes on
in a controller, you shouldn't set a title of an html page in a
controller. The method yield(:title) looks for the value of a title
variable in the view, which can be set like this:

<% provide(:title, "Home") %>

> New: "#{base_title} | Home"
> Old: @base_title + "| Home"

Those statements do the exact same thing in ruby. The first example
injects a second string into the first string. The second example joins
two strings together--producing a third string. So the second example is
a tiny bit more efficient.

--
Posted via http://www.ruby-forum.com/.

[rails2012]

Do you mean "#{base_title} | Home" is more efficient because it doesn't create a new String object? (You said second one... I am not sure if I got that right.)

(I wonder why I don't get email notifications when replies are sent...  I am pretty sure I clicked "Email updates to me"...)

[7stud --]

Well, if you are getting posts on the mailing list, then I guess you
don't get the edits, which are allowed for 15 minutes. I corrected that
error in my post--right after I posted.

[7stud --]

Derek Lin wrote in post #1075271:

> Do you mean "#{base_title} | Home" is more efficient because it doesn't
> create a new String object?
>

It certainly does create a new String object--that's what the quotes do;
they tell Ruby, "Please create a new String object for me. The
difference is that the following:

base_title + "| Home"

...creates two more String objects: "| Home" and another created by +.