Newbie: ternary "if" condition syntax on VIEW

Question

I would like to have the if condition logic like:

var == 10 ? “10″ : “Not 10″

on Rails VIEW. What I tried is following:

<%= session[:id]=="out"? link_to "Sign in", login_path : link_to "Sign out", logout_path%>

I know it looks odd, and unsurprisingly it does not work. So, if I would like to use ternary if condition on VIEW, what is the correct way to do in my case?

---------One more condition---------

I would like to have two "link_to" in else condition

-----The error message I got--------

compile error

syntax error, unexpected tSTRING_BEG, expecting kDO or '{' or '('
...ession[:id]=="out" ? link_to "Sign in",

Answer 1

Try this (the only diffrence is a space between " and ? and the use of parentheses)

<%= session[:id]=="out" ? link_to("Sign in", login_path) : link_to("Sign out", logout_path) %>

Altough parentheses are optional in Ruby they are needed to maintain operator precedence in some cases.

IMHO ternary operators are hard to read. You could also do something more verbose:

<%= link_to("Sign in", login_path) if session[:id] == "out" %>
<%= link_to("Sign out", logout_path) if session[:id] != "out" %>

Answer 2

session[:id]=="out"?

looks wrong. It should be

session[:id]=="out" ?

By the way if you need more link in the else part switch to an if else. It could be more clean:

<% if condition %>
  link
<% else %>
  link
  link
<% end %>