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Am 18.10.03 01:01 schröbte Reuben Thomas:
Did you try this code? I think it is what you might be looking for,
actually. Although you can do it with unpack() etc.

Yes, curry is simply:

-- curry: Partially apply a function
--   f: function to apply partially
--   a1 ... an: arguments to fix
-- returns
--   g: function with ai fixed
function curry (f, ...)
  local fix = arg
  return function (...)
           return f (unpack (fix), unpack (arg))

Your version does not work correctly.
If I say

local f = curry( print, 1, 2 )
f( 3, 4 )

I get:
1   3   4
but I should get
1   2   3   4

This is because only the first return value of unpack(fix) is used.
I got that problem with the following helper function:

local function dump( ... )
  io.stdout:write( unpack( arg ), "\n" )

which only printed the first argument.

For the curry function to work you will need some table merging:

function curry2( f, ... )
  local fix = arg
  return function( ... )
           local params = {}
           for _,a in ipairs( fix ) do
             table.insert( params, a )
           for _,a in ipairs( arg ) do
             table.insert( params, a )
           return f( unpack( params ) )

which is a lot simpler than messing around with C.