DSL for GTK2 in Nim

dsl_gtjk2.nim

import
  re, os, gtk2, gdk2, glib2, strutils, sequtils, math, typeinfo, macros
 

###################################### Engine 

############ Stack layout
var 
  gstack : seq[PBox] = @[] 
  glastWidget : PWidget

proc last[T](st: seq[T]) : T =
  result=st[st.high]
  
proc push[T](st: seq[T], e: T) : T =
  st.add(e)
  result=e
# pop already defined ...

proc append(w: PWidget) : void =
  glastWidget=w
  gstack.last.pack_start(w,true,true,0)

proc appendi(w: PWidget): void =
  glastWidget=w
  gstack.last.pack_start(w,false,false,0)

proc option() =
  echo("coucou")

############
template gtk_app(title: string,width,height: int,code: stmt): stmt {.immediate.} =
  nim_init()
  let  win = window_new(gtk2.WINDOW_TOPLEVEL)
  let content = vbox_new(true,10)
  win.set_title("Gtk: " & title)
  win.set_default_size(width,height)
  gstack.add(content)
  code 
  win.add(content)
  win.show_all()
  discard signal_connect(win, "destroy", SIGNAL_FUNC(mainQuit), nil)
  main()

proc mainQuit(widget: PWidget, data: Pgpointer) {.cdecl.} =
  main_quit()
 
  
######################################## Layout

template stack(code: stmt): stmt {.immediate.} =
  let content = vbox_new(false,0)
  append(content)
  apply(content,code)
  
template flow(code: stmt): stmt {.immediate.} =
  let content = hbox_new(false,0)
  append(content)
  apply(content,code)

template stacki(code: stmt): stmt {.immediate.} =
  let content = vbox_new(false,0)
  appendi(content)
  apply(content,code)
  
template flowi(code: stmt): stmt {.immediate.} =
  let content = hbox_new(false,30)
  appendi(content)
  apply(content,code)

template apply(w:PBox,code: stmt) : stmt {.immediate.} =
  gstack.add(w)
  code
  discard gstack.pop()

  
################################################## Widgets
proc nulproc() =
  echo("e")

proc button(label: string, f = nulproc) =
  var btn = button_new()
  if  (label.existsFile()) or  (label.find(re"^gtk-") > -1):
    var w= if existsFile(label): 
        image_new_from_file(label) 
      else: 
        imageNewFromStock(label, ICON_SIZE_BUTTON)
    btn.set_image(w)
  else:
    btn= button_new(label)
  if f!=nulproc:
    discard btn.signal_connect("pressed", SIGNAL_FUNC(f), btn)
  append( btn )

proc label(label: string)  =
  append( label_new(label) )
  
proc image(name: string)  =
  var w= if existsFile(name): 
      image_new_from_file(name) 
    else: 
      imageNewFromStock(name, ICON_SIZE_BUTTON)
  append( w )
  
proc buttoni(label: string, f = nulproc) =
  let btn = button_new(label)
  if f!=nulproc:
    discard btn.signal_connect("pressed", SIGNAL_FUNC(f), btn)
  appendi( btn )
  
proc labeli(label: string)  =
  appendi(label_new(label))

################################################################
#            M A I N
################################################################

"Test gui".gtk_app(0,200):
  stack:
    button "Aeeee ",proc () = 
      echo("eee")
      echo(".")
    flowi:
      button  "gtk-open",proc () = (echo "button image!!") 
      image  "gtk-close" 
      image  "gtk-help" 
    labeli  "RRRRR " 
    flowi:
      labeli "A "
      labeli "B "
      flowi:
          button "e",proc () =  (echo("eee") ; echo("aaa"))
          button "r"
      label "C---- "
    buttoni "\nExit\n",proc () =  (main_quit())