Re: Lua Cookbook

[Sean Conner <sean@...>]

It was thus said that the Great Marc Balmer once stated:
> Guys, we are talking about licenses and stuff.  But we should write recipes.
> 
> What the fuck is wrong with us?  IANAL, GPL, MIT, CC3A, WHATEVER.
> 
> I write a piece of text.  I am the author.  I own the copyright for the
> next 70 years.  I allow the "Lua Cookbook" project to use my text for
> inclusion in an electronic or paper version of the Cookbook.
> 
> Do we want to continue talking fucking legalese stuff none of us
> understands really or do we start to do the job and write that cookbook?

  So, a sample "recipie" for the Cookbook:

Recipie #1
Pretty Print The Contents Of A Table (non-recursive)
	Author:  Sean Conner	
	Website: http://example.net/lua/table/show.lua
	License: LGPL

The following function takes a table and prints out the contents of each
entry, formatted for a terminal width of 80 characters.  Given a nil, it
will print out the contents of _G (the global environment).  Possibly more
verbiage here and what not ... 

function show(l)
  local l = l or _G
  local maxkeylen = 0
  local maxvallen = 0
  
  local function conv_cntl(s)
    if s == "\n" then
      return "\\n"
    else
      return "\\?"
    end
  end
  
  for k,v in pairs(l)
  do
    maxkeylen = math.max(maxkeylen,string.len(tostring(k)))
    maxvallen = math.max(maxvallen,string.len(string.format("%q",tostring(v))))
  end
  
  ----------------------------------------------------
  -- clip the value portion to both the key and the
  -- value will display without wrapping in an 80
  -- column screen.  Also, the Lua runtime does not
  -- support formats longer than 99 characters wide.
  -----------------------------------------------------
  
  maxkeylen = math.min(30,maxkeylen)
  maxvallen = math.min(77 - maxkeylen,maxvallen)
  
  local format = string.format("%%-%ds %%-%ds",maxkeylen + 1,maxvallen + 1)
  
  for k,v in pairs(l)
  do
    local vt
    
    if type(v) == "string" then
      vt = string.format("%q",v)
    else
      vt = tostring(v)
    end
    
    vt = string.gsub(vt,"%c",conv_cntl)
    vt = string.sub(vt,1,maxvallen)
    print(string.format(format,tostring(k),vt))
  end
end

Sequences of recipies can be grouped by topic (say, manipulating tables,
processing strings, etc).

  -spc