Entry tags:

io

markaby-like html generation in io
i'm working on a little DSL for making HTML using Io. Here's what it looks like

html(
  head(
    title("ryan's web page")
  ) 
  body(
    h1("ryan!")
    br
    form(action="/guestbook",
      h2("sign my guest book!")
      p(
        label(for="name","name")
        input(type="text",name="name")
      )
      p(
        label(for="msg","msg")
        input(type="text",name="msg")
      )
      input(type="submit",value="sign")
    )
  )
)

Currently functional at 80 lines of code. For this I intercept each function call before it does anything, walk through it's argument list and see if it's a single = expression. These are stored as attributes. The last argument of the function is evaluated and added as children. Here is what it looks like

  TagCreator := block (
    args := call message arguments
    attr := Object clone

    # Parse the arguments of the function into
    # attributes and body.
    innerHTML_msg := nil
    args foreach(arg, 
      if( arg isSingular and arg name == "updateSlot"
        , name := arg argAt(0) cachedResult
          value := call sender doMessage(arg argAt(1))
          attr setSlot(name, value)
        , innerHTML_msg = arg
        )
    )
    
    element := Element clone
    element name := call message name
    element parent := call sender
    element attr := attr

    if( element parent hasSlot("children")
      , element parent children append(element)
      )

    if( innerHTML_msg
      , r := doMessage(innerHTML_msg, element)
        if(r type != "Element", element children append(r))
      )
    element
  )

Then for each tag-function i clone TagCreator

  html := TagCreator clone setIsActivatable(true)
  head := TagCreator clone setIsActivatable(true)
  body := TagCreator clone setIsActivatable(true)
  ...

I'll post the complete code once I get a chance to clean it up a bit.