Fire.app Feature Tutorial

Introducing Template Language: ERB

Fire.app provides many template languages to simplify HTML development.
We choose to introduce ERB here because ERB is actually "HTML with embedded Ruby." Those good with HTML will find ERB is easy to get familiar with.

With Fire.app we can easily use the template language by adding a corresponding file extension. For example, ERB uses this file extension .html.erb.

The three common ways to insert RUBY into ERB are listed below:

Only executes Ruby code and does not output results into HTML:

<% Ruby code... %>

Use an equal sign = to execute Ruby code and output results into HTML.

<%= Ruby code... %>

Use a sharp sign # to write a comment.

<%# Comment... %>

In addition, there are three commonly used functions:

If...else conditional

<% if condition %>  
  This part will be executed if condition is true
<% else %>
  This part will be executed if condition is false
<% end %>

For example:

<% if (1+1==2) %>  
  This line will be displayed.
<% else %>
  This line will never be displayed.
<% end %>

Because the condition 1+1==2 is always true, the result of the code above will be This line will be displayed. no matter what time it runs.

Do something for n times

<% n.times do %>  
  do something
<% end %>

For example:

<% 3.times do %>  
  Good morning! 
<% end %>

The result of the code above will be Good morning! Good morning! Good morning! .

Generating a number from 0 to n-1 randomly

<%= rand(n) %>

For example:

<%= rand(3) %>

The result of the code above could be 0, 1 or 2.