Universal template compiler based on ruby dynamic evaluation feature. Minimalistic design, customizable tokens, comments support, easy debugging.
For example this document was rendered from readme.md.rbs template.
gem install rebus
Rules are:
- input is interpreted line by line
- initial white spaces are ignored
- there are 3 different line types recognized by the following prefixes:
-
#- a comment line skipped during compilation -
|>- a code line evaluated during compilation - any other prefix - a string line with possible interpolated code (see Ruby string interpolation rules)
-
Sample (stealed and translated from ERB documentation):
Template(Rebus - HTML):
<html>
<head><title>Ruby Toys -- #@name</title></head>
<body>
<h1>#@name (#@code)</h1>
<p>#@desc</p>
<ul>
|> @features.each do |f|
<li><b>#{f}</b></li>
|> end
</ul>
<p>
|> if @cost < 10
<b>Only #@cost!!!</b>
|> else
Call for a price, today!
|> end
</p>
</body>
</html>Source code(Ruby):
require 'rebus'
require 'modeling' # to keep sample code concise
class Product
model :@code, :@name, :@desc, :@cost do
@features = [ ]
end
def add_feature( feature )
@features << feature
end
end
toy = Product.new( "TZ-1002",
"Rubysapien",
"Geek's Best Friend! Responds to Ruby commands...",
999.95 )
toy.add_feature("Listens for verbal commands in the Ruby language!")
toy.add_feature("Ignores Perl, Java, and all C variants.")
toy.add_feature("Karate-Chop Action!!!")
toy.add_feature("Matz signature on left leg.")
toy.add_feature("Gem studded eyes... Rubies, of course!")
puts Rebus.compile_file "a0.rbs", toyOutput(HTML):
<html>
<head><title>Ruby Toys -- Rubysapien</title></head>
<body>
<h1>Rubysapien (TZ-1002)</h1>
<p>Geek's Best Friend! Responds to Ruby commands...</p>
<ul>
<li><b>Listens for verbal commands in the Ruby language!</b></li>
<li><b>Ignores Perl, Java, and all C variants.</b></li>
<li><b>Karate-Chop Action!!!</b></li>
<li><b>Matz signature on left leg.</b></li>
<li><b>Gem studded eyes... Rubies, of course!</b></li>
</ul>
<p>
Call for a price, today!
</p>
</body>
</html>require 'rebus'
template = <<~'EOS'
<ul>
|> 3.times do
<li>!</li>
|> end
</ul>
EOS
puts Rebus.compile template
# Output:
#
# <ul>
# <li>!</li>
# <li>!</li>
# <li>!</li>
# </ul>require 'rebus'
template = <<~'EOS'
<ul>
# this is commented line - parser skip it
|> i = "Hello"
# |> (1..5).each do |i|
<li>#{i}</li>
# |> end
</ul>
EOS
puts Rebus.compile template
# Output:
#
# <ul>
# <li>Hello</li>
# </ul>require 'rebus'
puts Rebus.compile DATA
# Output:
#
# <ul>
# <li>1</li>
# <li>2</li>
# <li>3</li>
# </ul>
__END__
<ul>
|> (1..3).each do |i|
<li>#{i}</li>
|> end
</ul>require 'rebus'
items = [:a, :b, :c]
puts Rebus.compile DATA, binding
# Output:
#
# <ul>
# <li>a</li>
# <li>b</li>
# <li>c</li>
# </ul>
__END__
<ul>
|> items.each do |i|
<li>#{i}</li>
|> end
</ul>require 'rebus'
items = [:a, :b, :c]
Rebus.compile DATA do |line|
puts line
end
# Output:
#
# <ul>
# <li>a</li>
# <li>b</li>
# <li>c</li>
# </ul>
__END__
<ul>
|> items.each do |i|
<li>#{i}</li>
|> end
</ul>require 'rebus'
class Foo
def items
[:alpha, :beta, :gamma]
end
end
foo = Foo.new
puts Rebus.compile DATA, foo
# Output:
#
# <ul>
# <li>alpha</li>
# <li>beta</li>
# <li>gamma</li>
# </ul>
__END__
<ul>
|> items.each do |i|
<li>#{i}</li>
|> end
</ul>require 'rebus'
puts Rebus.compile DATA, items: [:alpha, :beta, :gamma]
# Output:
#
# <ul>
# <li>alpha</li>
# <li>beta</li>
# <li>gamma</li>
# </ul>
__END__
<ul>
|> items.each do |i|
<li>#{i}</li>
|> end
</ul>require 'rebus'
items = [:a, :b, :c]
puts Rebus.compile_file "b.html.rbs", binding
# Output:
#
# <ul>
# <li>a</li>
# <li>b</li>
# <li>c</li>
# </ul>b.html.rbs content:
<ul>
|> items.each do |i|
<li>#{i}</li>
|> end
</ul>require 'rebus'
items = [:a, :b, :c]
Rebus.home = __dir__
puts Rebus.compile_file "b.html.rbs", items: [:a, :b, :c]
# Output:
#
# <ul>
# <li>a</li>
# <li>b</li>
# <li>c</li>
# </ul>require 'rebus'
puts Rebus.compile_file "b.html.rbs"
# Output:
#
# .../sample/b.html.rbs:2: undefined local variable or method `items'...require 'rebus'
Rebus.code_prefix = "%"
Rebus.comment_prefix = "//"
puts Rebus.compile DATA
# Output:
#
# <ul>
# <li>1</li>
# <li>2</li>
# <li>3</li>
# </ul>
__END__
<ul>
% (1..3).each do |i|
// this is comment line
<li>#{i}</li>
// <br>
% end
</ul>- Łukasz Pomietło (oficjalnyadreslukasza@gmail.com)
