Summary

The functions provided by the SICStus Prolog Tcl/Tk library can be grouped in two ways: by function, and by package.

By function, we can group them like this:

• basic functions

  tcl_new/1

  create a Tcl interpreter
  

  tcl_delete/1

  remove a Tcl interpreter
  

  tk_new/2

  create a Tcl interpreter with Tk extensions

• evaluation functions

  tcl_eval/3

  evaluate a Tcl expression from Prolog
  

  prolog

  evaluate a Prolog expression from Tcl

• Prolog event queue functions

  tcl_event/3

  evaluate a Tcl expression and return a Prolog queue event list
  

  tk_next_event/[2,3]

  pass control to Tk until a Prolog queue event happens and return the head of the queue
  

  prolog_event

  place a Prolog term on the Prolog event queue from Tcl

• servicing Tcl and Tk events

  tk_do_one_event/[0,1]

  pass control to Tk until one Tk event is serviced
  

  tk_next_event/[2,3]

  also services Tk events but returns when a Prolog queue event happens and returns the head of the queue

• passing control completely to Tk

  tk_main_loop/0

  control passed to Tk until all windows in all Tcl/Tk interpreters are gone

• housekeeping

  tk_main_window/2

  return reference to main in of a Tcl/Tk interpreter
  

  tk_destroy_window/1

  destroy a window or widget
  

  tk_make_window_exist/1

  force display of a window or widget
  

  tk_num_main_windows/1

  return a count of the total number of Tk main windows existing in the system

By package, we can group them like this:

• predicates for Prolog to interact with Tcl interpreters

  tcl_new/1

  create a Tcl interpreter
  

  tcl_delete/1

  remove a Tcl interpreter
  

  tcl_eval/3

  evaluate a Tcl expression from Prolog
  

  tcl_event/3

  evaluate a Tcl expression and return a Prolog event list

• predicates for Prolog to interact with Tcl interpreters with Tk extensions

  tk_new/2

  create a Tcl interpreter with Tk extensions
  

  tk_do_one_event/[0,1]

  pass control to Tk until one Tk event is serviced
  

  tk_next_event/[2,3]

  also services Tk events but returns when a Prolog queue event happens and returns the head of the queue
  

  tk_main_loop/0

  control passed to Tk until all windows in all Tcl/Tk interpreters are gone
  

  tk_main_window/2

  return reference to main in of a Tcl/Tk interpreter
  

  tk_destroy_window/1

  destroy a window or widget
  

  tk_make_window_exist/1

  force display of a window or widget
  

  tk_num_main_windows/1

  return a count of the total number of Tk main windows existing in the system

• commands for the Tcl interpreters to interact with the Prolog system

  prolog

  evaluate a Prolog expression from Tcl
  

  prolog_event

  place a Prolog term on the Prolog event queue from Tcl

In the next section we will discuss how to use the tcltk library to build graphical user interfaces to Prolog applications. More specifically we will discuss the ways in which cooperation between Prolog and Tcl/Tk can be arranged: how to achieve them, and their benefits.