Tcl/Tk Go bindings.

VERSION NOTICE

Recently Tcl/Tk 8.6 were released. I use them as a default, if you still have
Tcl/Tk 8.5 use `go get -tags tcl85 github.com/nsf/gothic`.

DESCRIPTION

In its current state the bindings are a bit Tk-oriented. You can't create an
interpreter instance without Tk. In future it's likely it will be changed.

The API is very simple. In the package you have one type and one function:

type Interpreter struct
func NewInterpreter (init interface{}) *Interpreter

In order to launch an interpreter you have to call the "NewInterpreter"
function, it will make a new instance of a tcl/tk interpreter in a separate
goroutine, execute "init", block in Tk's main loop and then the function
returns a pointer to the new instance of an "Interpreter".

"init" could be a string with tcl commands that are executed before Tk's main
loop, or a function with this signature: "func (*Interpreter)". This function
gets executed the same way as the string, that is - before Tk's main loop.

Here are the methods of the "Interpreter":

func (*Interpreter) ErrorFilter(filt func(error) error)
func (*Interpreter) Eval(args ...interface{}) error
func (*Interpreter) EvalAs(out interface{}, args ...interface{}) error
func (*Interpreter) Set(name string, val interface{}) error
func (*Interpreter) UploadImage(name string, img image.Image) error
func (*Interpreter) RegisterCommand(name string, cbfunc interface{}) error
func (*Interpreter) UnregisterCommand(name string) error
func (*Interpreter) RegisterCommands(name string, val interface{}) error
func (*Interpreter) UnregisterCommands(name string) error

As it was stated before, the "Interpreter" is being executed in a separate
goroutine and each method is completely thread-safe. Also every method is
synchronous. It will queue commands for execution and wait for their
completion.

That's it. See "examples" directory it has the use cases for most of the API.