Template language idea

template.zen

/*
 * 'Zenplate': a language/template-engine agnostic markup DSL
 */

// extending a zenplate
extend -> 'base.zen'

// support for extending templates from other template engines
extend -> jinja 'base.j2'

// support for extending any of your existing templates;
// the template that will actually be extended will depend 
// on the output format you choose.

extend ->
  jinja 'base.j2'
  mako  'base.mako
  php   'base.php'

// the '->' operator signifies a zenplate directive (in this case, 'extend')
// and the arguments that are to be passed to the directive, are to the right of it.


doctype 5
html lang="en"
  head
    // variables start with a '@'
    title @my_title_var
    meta charset="utf-8"

  body
    div #id .(class1 class2)
      some simple text here

    // keywords ending in ':' are filters.
    markdown:
      simple _markdown_ filter


    // '::' is the include operator. Used for including content from external files, 
    // and passing them to a filter
    markdown:: 'file.md'
      with -> extension1, extension2

      // the 'with' keyword signifies a list of parameters/extensions that are
      // to be passed to the filter. May be placed in the same line as the filter directive,
      // or indented, one line below it.


    // alternatively, arguments may be passed this way as well
    markdown(extension1, extension2):: 'file.md'

    
    // include a jinja template
    jinja:: 'template.j2'
      // indented text below an include directive (aside from special kewords/arguments)
      // will produce an error.

    // here's another way to include a jinja template
    include -> jinja 'template.zen'

    // 'include' works on zenplates by default
    include -> 'template2.zen'

    // designate a zen block
    block -> content
        text text text...

    // designate a template-specific block
    block -> jinja content
        you could even use {{ template_specific_syntax }} in these blocks


    
    this is an span[inline] element.
    
    this is an span(id="span")[inline] element with attributes.

    span  this whole line is in an inline element    

    and these are self-closing elements: img(res="image.jpg") br
    

    this is an upper:[inline] filter.

    and this is an inline filter with substring(0,3):[without] arguments



    // element attributes may be surrounded by'( )', but this is optional, 
    // unless they are inline elements.

    div(id="content" class="text")
        text text text

    // is the same as:

    div id="content" class="text"
        text text text

    // and using shorthand:

    div #content .(text)
       text text text

    // class shorthand uses '.( )' to make it easier to denote a list of classes
    // and id uses the traditional '#' shorthand. Shorthands must all have a space in between them;
    // they may not be chained together like in haml.

    // div's must be explicitly stated by default.
   
    this text will not be contained in a div

    div
      but this text will


    // content for block-elements must always start in a new line, and be indented
    p
      all this text will go 
      under the <p> element

    

    // variable declarations
    @some_var = "some value"

    // if you want that literal text in your html, just escape it:
    \@some_var = "some value"


    // call the variable's methods
    - if @some_link.startswith("http://")
        a(href="@some_link")[ go here ]

    // call a function
    - if not isempty(@some_list)
      ul
        - for @item in @some_list
          li @item