Home

Awesome

tagg

Build Status Gitter

markup as coffeescript (again)

Motivation

The brevity of coffeescript lends itself well to writing markup templates in a style that resembles jade. This has been done before. However tagg eschews preprocessing and builder objects in favour of destructuring assignment.

Installing with NPM

```bash` npm install -S tagg


Use destructuring assignment to pick out the wanted tags.

```coffee
{div, p, img} = require 'tagg'

div class:'special', ->
    p 'some text', -> img(src:'/pic.jpg')

Installing with Bower

bower install -S tagg

This exposes the global object tagg.

Use destructuring assignment to pick out the wanted tags.

{div, p, img} = tagg

div class:'special', ->
    p 'some text', -> img(src:'/pic.jpg')

Example

We have a list of cute pandas:

pandas = [
    {src:'/panda1.jpg', desc:'Cute baby panda'}
    {src:'/panda2.jpg', desc:'Panda with straw'}
    {src:'/panda3.jpg', desc:'Sleeping panda'}
]

The following pure coffeescript code:

{html5, head, meta, title, script, body, p, ol, li, img} = require 'tagg'

html5 ->
    head ->
        meta charset:'utf-8'
        title 'Forever Panda'
        script src:'/js/jquery.min.js'
    body ->
        p 'Funny panda compilation, puppies & kitties:'
        ol ->
            li (->img src:p.src), p.desc for p in pandas

Generates this output:

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Forever Panda</title>
    <script src="/js/jquery.min.js"></script>
  </head>
  <body>
    <p>Funny panda compilation, puppies &amp; kitties:</p>
    <ol>
      <li><img src="/panda1.jpg">Cute baby panda</li>
      <li><img src="/panda2.jpg">Panda with straw</li>
      <li><img src="/panda3.jpg">Sleeping panda</li>
    </ol>
  </body>
</html>

API

[tag] a1, a2, a3, ...

All tags work exactly the same.

Arguments are objects, functions and strings

Tags takes a variadic argument list and does:

  1. Any object argument {k:v} is treated as a tag attribute specification.
  2. Any function argument f will be rendered as a child element.
  3. Any string argument s will be wrapped -> s and treated as a function argument (2).

Order of attribute object is irrelevant

The arguments can be in any order. Attributes are (naturally) dealt with first. It is entirely possible to do:

p 'some text', class:'explicit'     # <p class="explicit">some text</p>

Order of functions/strings is preserved

Strings and functions are dealt with in the declared order:

p 'some', ' ', (-> 'text'), ' ', (-> img(src:'/panda.jpg')), ' after'

Will render:

<p>some text <img src="/panda.jpg"> after</p>

Special pass tag

The pass tag is useful in instances where you want to have a tag that follows the standard tag function unnesting logic, but doesn't produce a tag output itself.

pass 'some ', -> pass 'text'

Will render:

some text

Single render thread

When rendering with tagg, all output must be done in one go. No setTimeout, no ajax, no callbacks.

# THIS DOES NOT WORK!!!!
p 'Waiting for ajax: ' ->
    $.ajax('/something').done(->'done')

Make your own tag

Not happy with the builtins? Make your own!

The library exports a function tag(name,isVoid) which can be used to make your own tags. Set isVoid to true to define a void element, like img, that has no closing tag.

{tag} = require 'tagg'
special = tag 'special'

special class:'sweet', 'thing'

Renders to:

<special class="sweet">thing</special>

Capture output

The default renders the tags to an HTML string, it is possible to capture output callbacks and create other representations instead.

This is done using the capture(out, fun, args) function exposed with:

{capture} = require 'tagg'

The function takes three argument. First is an out object with the methods:

This is an example of the default string output:

# default output, as string
class StringOut
    constructor: ->
        @buf = []
    start: ->
    begin: (name, vod, props) ->
        # push name and turn props into string attributes.
        @buf.push "<#{name}" +
            (if (a = attrs(props)).length then " " + a else "") + ">"
    text: (t) ->
        @buf.push esc(t)       # escape HTML text
    close: (name) ->
        @buf.push "</#{name}>"
    end: -> @buf.join('')      # return value for capture

The second argument is the function we want to invoke when building, and the third an optional array of arguments to pass to the second function.

Built ins

Built in tags

The built in tags are taken from mozilla element page apart from those listed as obsolote and deprecated. The full list is easiest to see in the source.

Void elements

Tagg is aware of void elements, like <img> and <meta> – elements which do not need a close tag. The list of such attributes are in the source.

Boolean attributes

Boolean attributes are those whose presence indicates a true value, like checked in <input type="checkbox" checked>. Tagg has a built in list of such attributes, and will not output any value for them.

The map value for such properties are used as truthy/falsey, i.e.

input type:checkbox, checked:true
select ->
    option selected:false, 'panda'
    option selected:'yes', 'kitten'

Will render:

<input type="checkbox" checked>
<select>
    <option>panda</option>
    <option selected>kitten</option>

Empty string is falsey

Notice that javascript defines empty string "" as falsey, so (maybe surprisingly) input type:checkbox, checked:'' will output <input type="checkbox">

Not tag aware

Tagg does not keep track of which attribute belongs to which tag. So (although it makes no semantic sense) p checked:true will render as <p checked>.

License

The MIT License (MIT)

Copyright © 2015 Martin Algesten

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.