iq-scm / mote

Minimum Operational Template

Mote

Minimum Operational Template.

Description

Mote is a very simple and fast template engine.

Usage

Usage is very similar to that of ERB:

template = Mote.parse("This is a template")
template.call #=> "This is a template"

Silly example, you may say, and I would agree. What follows is a short list of the different use cases you may face:

% # This is a comment
% if user == "Bruno"
  {{user}} rhymes with Piano
% elsif user == "Brutus"
  {{user}} rhymes with Opus
% end

<?
  # Multiline code evaluation
  lucky = [1, 3, 7, 9, 13, 15]
  prime = [2, 3, 5, 7, 11, 13]
?>

{{ lucky & prime }}

Control flow

Lines that start with % are evaluated as Ruby code. Anything between <? and ?>, including new lines, is also evaluated as Ruby code.

Assignment

Whatever it is between {{ and }} gets printed in the template.

Comments

There's nothing special about comments, it's just a # inside your Ruby code:

% # This is a comment.

Block evaluation

As with control instructions, it happens naturally:

% 3.times do |i|
  {{i}}
% end

Parameters

The values passed to the template are available as local variables:

example = Mote.parse("Hello {{name}}", self, [:name])
assert_equal "Hello world", example.call(name: "world")
assert_equal "Hello Bruno", example.call(name: "Bruno")

Please note that the keys in the parameters hash must be symbols.

Helpers

There's a helper available in the Mote::Helpers module, and you are free to include it in your code. To do it, just type:

include Mote::Helpers

Using the mote helper

The mote helper receives a file name and a hash and returns the rendered version of its content. The compiled template is cached for subsequent calls.

assert_equal "***\n", mote("test/basic.mote", n: 3)

Template caching

When the mote helper is first called with a template name, the file is read and parsed, and a proc is created and stored in the current thread. The parameters passed are defined as local variables in the template. If you want to provide more parameters once the template was cached, you won't be able to access the values as local variables, but you can always access the params hash.

For example:

# First call
mote("foo.mote", a: 1, b: 2)

Command line tool

Mote ships with a command line tool to render mote templates. The result is redirected to standard output.

mote FILE [param1 value1 ... paramN valueN]

The extra parameters supplied will be passed to the template. Note that all the parameter values will be treated as strings.

Example usage

If your template is called foo.mote, you can render it with the following command:

mote foo.mote

To write the result to a new file, just redirect the output:

mote foo.mote > foo.html

If the template uses a local variable bar, you can pass a value from the command line:

mote foo.mote bar 42

Installation

You can install it using rubygems.

$ gem install mote