scopes.coffee

exposed_scope = {}
top_scope = null

push_scope = ->
  top_scope = exposed_scope.__proto__ = Object.create exposed_scope.__proto__

pop_scope = ->
  top_scope = exposed_scope.__proto__ = exposed_scope.__proto__.__proto__

with_scope = (fn) ->
  push_scope()
  try
    fn()
  finally
    pop_scope()

window.importing = (vars, fn) ->
  console.log 'importing', vars
  with_scope ->
    top_scope[k] = v for k, v of vars
    fn()

window.run_dsl = (fn) ->
  with_scope ->
    `with (exposed_scope) {`
    eval("(#{fn.toString()})")()
    `}`

####################################

tag_names = 'div p strong em'.split ' '

create_tag = (t) ->
  console.log t
  tag = document.createElement t
  tag.innerText = t
  tag

nested_tag = (parent, name) ->
  tag = create_tag name
  parent.add_child tag
window.tags = {}

create_nesting_tags = (parent) ->
  nested_tags = {}
  for t in tag_names
    do (t) ->
      nested_tags[t] = (fn) ->
        tag = create_tag t
        parent.appendChild tag
        if fn?
          importing create_nesting_tags(tag), fn
        console.log 'adding', tag, 'to', parent
        tag
  nested_tags

for t in tag_names
  do (t) ->
    tags[t] = (fn) ->
      tag = create_tag t
      if fn?
        importing create_nesting_tags(tag), fn
      tag

####################################
output = (o) -> run_context.output o

run_dsl ->
  importing tags, ->
    output div ->
      p ->
        em()
        strong()