raw vs. html_safe vs. h to unescape html
erb, ruby-on-rails
Solution
Considering Rails 3:
`html_safe` actually "sets the string" as HTML Safe (it's a little more complicated than that, but it's basically it). This way, you can return HTML Safe strings from helpers or models at will.
`h` can only be used from within a controller or view, since it's from a helper. It will force the output to be escaped. It's not really deprecated, but you most likely won't use it anymore: the only usage is to "revert" an `html_safe` declaration, pretty unusual.
Prepending your expression with `raw` is actually equivalent to calling `to_s` chained with `html_safe` on it, but is declared on a helper, just like `h`, so it can only be used on controllers and views.
"SafeBuffers and Rails 3.0" is a nice explanation on how the `SafeBuffer`s (the class that does the `html_safe` magic) work.
Problem
Suppose I have the following string ``` @x = "<a href='#'>Turn me into a link</a>" ``` In my view, I want a link to be displayed. That is, I don't want everything in @x to be unescaped and displayed as a string. What's the difference between using ``` <%= raw @x %> <%= h @x %> <%= @x.html_safe %> ``` ?