Scite Lua Prompt

wiki

Interactive SciTE Lua

This is a little script which uses the SciteExtMan script manager and is one of the examples in the download.

It uses the extman scite_OnOutputLine event to grab lines entered in SciTE's output pane, and compile them using loadstring. It gives you a very useful way to interactively evaluate Lua expressions. One-line functions can be defined.

Scite/Lua

> = 10 + 20

30

> print 'hello dolly'

hello dolly

> function showkeys(t) for i in t do print(i) end end

> showkeys(table)

setn

insert

getn

foreachi

foreach

sort

remove

concat

> 

Event if you don't see yourself as doing Lua programming, this Lua prompt is useful as an intelligent calculator.

Any global function is available. A function load is supplied, which will load Lua code from a file. If called with no argument, it will use the current buffer. The function edit will open the specified file in a new buffer. There is pop-down history list available using Tools|Last Command, which is Ctrl-Alt-P.

It is particularly useful for learning the SciTE and Scintilla API, since both the editor and output pane objects are directly accessible. You can test a particular operation before writing a full-blown script.

> = output.Length

405

> output:AppendText('hello, world!\n')

hello, world!

> 

Issues

The SciTE Lua environment has a nasty suprise for people expecting global objects to survive for the whole session. If you switch buffers in SciTE, the global environment is cleared out. Only global objects created initially in files loaded by your Lua startup script will be preserved.

Source

 -- prompt.lua

 scite_Command('Last Command|do_command_list|Ctrl+Alt+P')



 local prompt = '> '

 local history_len = 4

 local prompt_len = string.len(prompt)

 print 'Scite/Lua'

 trace(prompt)



 function load(file)

	if not file then file = props['FilePath'] end

	dofile(file)

 end



 function edit(file)

	scite.Open(file)

 end



 local sub = string.sub

 local commands = {}



 local function strip_prompt(line)

   if sub(line,1,prompt_len) == prompt then

        line = sub(line,prompt_len+1)

    end	

	return line

 end

  

 scite_OnOutputLine (function (line)

	line = strip_prompt(line)

   table.insert(commands,1,line)

    if table.getn(commands) > history_len then

        table.remove(commands,history_len+1)

    end

    if sub(line,1,1) == '=' then

        line = 'print('..sub(line,2)..')'

    end    

    local f,err = loadstring(line,'local')

    if not f then 

      print(err)

    else

      local ok,res = pcall(f)

      if ok then

         if res then print('result= '..res) end

      else

         print(res)

      end      

    end

    trace(prompt)

    return true

end)



function insert_command(cmd)

	output:AppendText(cmd)

	output:GotoPos(output.Length)

end



function do_command_list()

     if table.getn(commands) > 1 then 

		scite_UserListShow(commands,1,insert_command)

     end

end