class Mustache

Mustache is the base class from which your Mustache subclasses should inherit (though it can be used on its own).

The typical Mustache workflow is as follows:

Create a Mustache subclass: class Stats < Mustache
Create a template: stats.mustache
Instantiate an instance: view = Stats.new
Render that instance: view.render

You can skip the instantiation by calling `Stats.render` directly.

While Mustache will do its best to load and render a template for you, this process is completely customizable using a few options.

All settings can be overriden at the class level.

For example, going with the above example, we can use `Stats.template_path = "/usr/local/templates"` to specify the path Mustache uses to find templates.

Here are the available options:

::template_path

The `::template_path` setting determines the path Mustache uses when looking for a template. By default it is "." Setting it to /usr/local/templates, for example, means (given all other settings are default) a Mustache subclass `Stats` will try to load /usr/local/templates/stats.mustache

::template_extension

The `::template_extension` is the extension Mustache uses when looking for template files. By default it is "mustache"

::template_file

You can tell Mustache exactly which template to us with this setting. It can be a relative or absolute path.

template

Sometimes you want Mustache to render a string, not a file. In those cases you may set the `template` setting. For example:

>> Mustache.render("Hello {{planet}}", :planet => "World!")
=> "Hello World!"

The `template` setting is also available on instances.

view = Mustache.new
view.template = "Hi, {{person}}!"
view[:person] = 'Mom'
view.render # => Hi, mom!

::view_namespace

To make life easy on those developing Mustache plugins for web frameworks or other libraries, Mustache will attempt to load view classes (i.e. Mustache subclasses) using the `::view_class` class method. The `::view_namespace` tells Mustache under which constant view classes live. By default it is `Object`.

::view_path

Similar to `::template_path`, the `::view_path` option tells Mustache where to look for files containing view classes when using the `::view_class` method.

Settings which can be configured for all view classes, a single view class, or a single Mustache instance.

Constants

Version

Public Class Methods

classify(underscored) click to toggle source

template_partial => TemplatePartial template/partial => Template::Partial

# File lib/mustache.rb, line 257
def self.classify(underscored)
  underscored.split('/').map do |namespace|
    namespace.split(%r[-_]/).map do |part|
      part[0] = part[0].chr.upcase; part
    end.join
  end.join('::')
end

compiled?() click to toggle source

Has this template already been compiled? Compilation is somewhat expensive so it may be useful to check this before attempting it.

# File lib/mustache.rb, line 246
def self.compiled?
  @template.is_a? Template
end

const_get!(name) click to toggle source

Supercharged version of Module#const_get.

Always searches under Object and can find constants by their full name,

e.g. Mustache::Views::Index

name - The full constant name to find.

Returns the constant if found Returns nil if nothing is found

# File lib/mustache.rb, line 236
def self.const_get!(name)
  name.split('::').inject(Object) do |klass, name|
    klass.const_get(name)
  end
rescue NameError
  nil
end

inheritable_config_for(attr_name, default) click to toggle source

Return the value of the configuration setting on the superclass, or return the default.

attr_name - Symbol name of the attribute. It should match the instance variable. default - Default value to use if the superclass does not respond.

Returns the inherited or default configuration setting.

# File lib/mustache.rb, line 301
def self.inheritable_config_for(attr_name, default)
  superclass.respond_to?(attr_name) ? superclass.send(attr_name) : default
end

partial(name) click to toggle source

Given a name, attempts to read a file and return the contents as a string. The file is not rendered, so it might contain {{mustaches}}.

Call `render` if you need to process it.

# File lib/mustache.rb, line 170
def self.partial(name)
  File.read("#{template_path}/#{name}.#{template_extension}")
end

path() click to toggle source

Alias for `::template_path`

# File lib/mustache/settings.rb, line 34
def self.path
  template_path
end

path=(path) click to toggle source

Alias for `::template_path`

# File lib/mustache/settings.rb, line 40
def self.path=(path)
  self.template_path = path
end

raise_on_context_miss=(boolean) click to toggle source

# File lib/mustache/settings.rb, line 181
def self.raise_on_context_miss=(boolean)
  @raise_on_context_miss = boolean
end

raise_on_context_miss?() click to toggle source

Should an exception be raised when we cannot find a corresponding method or key in the current context? By default this is false to emulate ctemplate's behavior, but it may be useful to enable when debugging or developing.

If set to true and there is a context miss, `Mustache::ContextMiss` will be raised.

# File lib/mustache/settings.rb, line 177
def self.raise_on_context_miss?
  @raise_on_context_miss
end

render(*args) click to toggle source

Instantiates an instance of this class and calls `render` with the passed args.

Returns a rendered String version of a template

# File lib/mustache.rb, line 83
def self.render(*args)
  new.render(*args)
end

Also aliased as: to_html, to_text

render_file(name, context = {}) click to toggle source

Given a file name and an optional context, attempts to load and render the file as a template.

# File lib/mustache.rb, line 155
def self.render_file(name, context = {})
  render(partial(name), context)
end

template() click to toggle source

The template is the actual string Mustache uses as its template. There is a bit of magic here: what we get back is actually a Mustache::Template object, but you can still safely use `template=`

with a string.

# File lib/mustache/settings.rb, line 141
def self.template
  @template ||= templateify(File.read(template_file))
end

template=(template) click to toggle source

# File lib/mustache/settings.rb, line 145
def self.template=(template)
  @template = templateify(template)
end

template_extension() click to toggle source

A Mustache template's default extension is 'mustache', but this can be changed.

# File lib/mustache/settings.rb, line 52
def self.template_extension
  @template_extension ||= inheritable_config_for :template_extension, 'mustache'
end

template_extension=(template_extension) click to toggle source

# File lib/mustache/settings.rb, line 56
def self.template_extension=(template_extension)
  @template_extension = template_extension
  @template = nil
end

template_file() click to toggle source

The template file is the absolute path of the file Mustache will use as its template. By default it's ./class_name.mustache

# File lib/mustache/settings.rb, line 111
def self.template_file
  @template_file || "#{path}/#{template_name}.#{template_extension}"
end

template_file=(template_file) click to toggle source

# File lib/mustache/settings.rb, line 115
def self.template_file=(template_file)
  @template_file = template_file
  @template = nil
end

template_name() click to toggle source

The template name is the Mustache template file without any extension or other information. Defaults to `class_name`.

You may want to change this if your class is named Stat but you want to re-use another template.

class Stat
  self.template_name = "graphs" # use graphs.mustache
end

# File lib/mustache/settings.rb, line 85
def self.template_name
  @template_name || underscore
end

template_name=(template_name) click to toggle source

# File lib/mustache/settings.rb, line 89
def self.template_name=(template_name)
  @template_name = template_name
  @template = nil
end

template_path() click to toggle source

The template path informs your Mustache view where to look for its corresponding template. By default it's the current directory (".")

A class named Stat with a ::template_path of "app/templates" will look for "app/templates/stat.mustache"

# File lib/mustache/settings.rb, line 15
def self.template_path
  @template_path ||= inheritable_config_for :template_path, '.'
end

template_path=(path) click to toggle source

# File lib/mustache/settings.rb, line 19
def self.template_path=(path)
  @template_path = File.expand_path(path)
  @template = nil
end

templateify(obj) click to toggle source

Turns a string into a Mustache::Template. If passed a Template, returns it.

# File lib/mustache.rb, line 282
def self.templateify(obj)
  if obj.is_a?(Template)
    obj
  else
    Template.new(obj.to_s)
  end
end

to_html(*args) click to toggle source

Alias for: render

to_text(*args) click to toggle source

Alias for: render

underscore(classified = name) click to toggle source

TemplatePartial => template_partial

Template::Partial => template/partial Takes a string but defaults to using the current class' name.

# File lib/mustache.rb, line 268
def self.underscore(classified = name)
  classified = name if classified.to_s.empty?
  classified = superclass.name if classified.to_s.empty?

  string = classified.dup.split("#{view_namespace}::").last

  string.split('::').map do |part|
    part[0] = part[0].chr.downcase
    part.gsub(%r[A-Z]/) { |s| "_#{s.downcase}"}
  end.join('/')
end

view_class(name) click to toggle source

When given a symbol or string representing a class, will try to produce an appropriate view class. e.g.

Mustache.view_namespace = Hurl::Views
Mustache.view_class(:Partial) # => Hurl::Views::Partial

# File lib/mustache.rb, line 204
def self.view_class(name)
  if name != classify(name.to_s)
    name = classify(name.to_s)
  end

  # Emptiness begets emptiness.
  if name.to_s == ''
    return Mustache
  end

  file_name = underscore(name)
  name = "#{view_namespace}::#{name}"

  if const = const_get!(name)
    const
  elsif File.exists?(file = "#{view_path}/#{file_name}.rb")
    require "#{file}".chomp('.rb')
    const_get!(name) || Mustache
  else
    Mustache
  end
end

view_namespace() click to toggle source

The constant under which Mustache will look for views when autoloading. By default the view namespace is `Object`, but it might be nice to set it to something like `Hurl::Views` if your app's main namespace is `Hurl`.

# File lib/mustache/settings.rb, line 203
def self.view_namespace
  @view_namespace ||= inheritable_config_for(:view_namespace, Object)
end

view_namespace=(namespace) click to toggle source

# File lib/mustache/settings.rb, line 207
def self.view_namespace=(namespace)
  @view_namespace = namespace
end

view_path() click to toggle source

Mustache searches the view path for .rb files to require when asked to find a view class. Defaults to "."

# File lib/mustache/settings.rb, line 219
def self.view_path
  @view_path ||= inheritable_config_for(:view_path, '.')
end

view_path=(path) click to toggle source

# File lib/mustache/settings.rb, line 223
def self.view_path=(path)
  @view_path = path
end

Public Instance Methods

[](key) click to toggle source

Context accessors.

view = Mustache.new view = "Jon" view.template = "Hi, {{name}}!" view.render # => "Hi, Jon!"

# File lib/mustache.rb, line 138
def [](key)
  context[key.to_sym]
end

[]=(key, value) click to toggle source

# File lib/mustache.rb, line 142
def []=(key, value)
  context[key.to_sym] = value
end

compiled?() click to toggle source

Has this instance or its class already compiled a template?

# File lib/mustache.rb, line 251
def compiled?
  (@template && @template.is_a?(Template)) || self.class.compiled?
end

context() click to toggle source

A helper method which gives access to the context at a given time. Kind of a hack for now, but useful when you're in an iterating section and want access to the hash currently being iterated over.

# File lib/mustache.rb, line 149
def context
  @context ||= Context.new(self)
end

escapeHTML(str) click to toggle source

Override this to provide custom escaping.

class PersonView < Mustache

def escapeHTML(str)
  my_html_escape_method(str)
end

end

Returns a String

# File lib/mustache.rb, line 190
def escapeHTML(str)
  CGI.escapeHTML(str)
end

partial(name) click to toggle source

Override this in your subclass if you want to do fun things like reading templates from a database. It will be rendered by the context, so all you need to do is return a string.

# File lib/mustache.rb, line 177
def partial(name)
  self.class.partial(name)
end

path() click to toggle source

Alias for: template_path

path=(path) click to toggle source

Alias for: template_path=

raise_on_context_miss=(boolean) click to toggle source

# File lib/mustache/settings.rb, line 190
def raise_on_context_miss=(boolean)
  @raise_on_context_miss = boolean
end

raise_on_context_miss?() click to toggle source

Instance level version of `::raise_on_context_miss?`

# File lib/mustache/settings.rb, line 186
def raise_on_context_miss?
  self.class.raise_on_context_miss? || @raise_on_context_miss
end

render(data = template, ctx = {}) click to toggle source

Parses our fancy pants template file and returns normal file with all special {{tags}} and {{sections}}replaced{{/sections}}.

data - A String template or a Hash context. If a Hash is given,

      we'll try to figure out the template from the class.
ctx - A Hash context if `data` is a String template.

Examples

@view.render("Hi {{thing}}!", :thing => :world)

View.template = "Hi {{thing}}!"
@view = View.new
@view.render(:thing => :world)

Returns a rendered String version of a template

# File lib/mustache.rb, line 108
def render(data = template, ctx = {})
  if data.is_a? Hash
    ctx = data
    tpl = templateify(template)
  elsif data.is_a? Symbol
    self.template_name = data
    tpl = templateify(template)
  else
    tpl = templateify(data)
  end

  return tpl.render(context) if ctx == {}

  begin
    context.push(ctx)
    tpl.render(context)
  ensure
    context.pop
  end
end

Also aliased as: to_html, to_text

render_file(name, context = {}) click to toggle source

Given a file name and an optional context, attempts to load and render the file as a template.

# File lib/mustache.rb, line 161
def render_file(name, context = {})
  self.class.render_file(name, context)
end

template() click to toggle source

The template can be set at the instance level.

# File lib/mustache/settings.rb, line 150
def template
  return @template if @template

  # If they sent any instance-level options use that instead of the class's.
  if @template_path || @template_extension || @template_name || @template_file
    @template = templateify(File.read(template_file))
  else
    @template = self.class.template
  end
end

template=(template) click to toggle source

# File lib/mustache/settings.rb, line 161
def template=(template)
  @template = templateify(template)
end

template_extension() click to toggle source

# File lib/mustache/settings.rb, line 61
def template_extension
  @template_extension ||= self.class.template_extension
end

template_extension=(template_extension) click to toggle source

# File lib/mustache/settings.rb, line 65
def template_extension=(template_extension)
  @template_extension = template_extension
  @template = nil
end

template_file() click to toggle source

The template file is the absolute path of the file Mustache will use as its template. By default it's ./class_name.mustache

# File lib/mustache/settings.rb, line 122
def template_file
  @template_file || "#{path}/#{template_name}.#{template_extension}"
end

template_file=(template_file) click to toggle source

# File lib/mustache/settings.rb, line 126
def template_file=(template_file)
  @template_file = template_file
  @template = nil
end

template_name() click to toggle source

# File lib/mustache/settings.rb, line 94
def template_name
  @template_name ||= self.class.template_name
end

template_name=(template_name) click to toggle source

# File lib/mustache/settings.rb, line 98
def template_name=(template_name)
  @template_name = template_name
  @template = nil
end

template_path() click to toggle source

# File lib/mustache/settings.rb, line 24
def template_path
  @template_path ||= self.class.template_path
end

Also aliased as: path

template_path=(path) click to toggle source

# File lib/mustache/settings.rb, line 28
def template_path=(path)
  @template_path = File.expand_path(path)
  @template = nil
end

Also aliased as: path=

templateify(obj) click to toggle source

# File lib/mustache.rb, line 290
def templateify(obj)
  self.class.templateify(obj)
end

to_html(data = template, ctx = {}) click to toggle source

Alias for: render

to_text(data = template, ctx = {}) click to toggle source

Alias for: render