V2.1: Number formatting

Hanami offers a helpful way to present numbers via #format_number helper method. It returns a formatted string for the given number.

If an integer is given, applies no precision in the returned string.
For all other kinds (Float, BigDecimal, etc.), formats the number as a float.

Usage

Here is how you can use it in templates:

<span><%= format_number(1_000_000) %></span>
<span><%= format_number(1_000_000.10) %></span>

This will render the number in the nice, readable form:

  <span>1,000,000</span>
  <span>1,000,000.00</span>

In parts, you can access your helpers via the helpers object.

Given you have a view exposure defined:

# app/views/books/show.rb

module Bookshelf
  module Views
    module Books
      class Index < Bookshelf::View
        expose :books do
          [
            Book.new(title: "Hanami")
            Book.new(title: "Hanami 2")
          ]
        end
      end
    end
  end
end

Then you can have the part with the helper used.

# app/views/parts/books.rb

module Bookshelf
  module Views
    module Parts
      module Books
        def formatted_count
          helpers.format_number(value.count)
        end
      end
    end
  end
end

Then in the template you can just access the part:

# app/templates/books/index.html.erb

<%= books.formatted_count %>

<span>1,000,000</span>

Precision

The default precision is of 2, but we can specify a different value with the homonym option.

format_number(Math::PI)               # => "3.14"
format_number(Math::PI, precision: 6) # => "3.141592"

Delimiter

The default thousands delimiter is ,. We can use :delimiter for a different char.

format_number(1_000_000)                 # => "1,000,000"
format_number(1_000_000, delimiter: '.') # => "1.000.000"

Separator

The default separator is .. We can use :separator for a different char.

format_number(1.23)                 # => "1.23"
format_number(1.23, separator: ',') # => "1,23"