Re: list files in dir recursively

Yes, that's what is written in docs. But why the following implementation does not work and returns an empty table? 

require "paths"

require "lfs"

function isdir(path)

  return lfs.attributes(path)["mode"] == "directory"

end

function deepfiles(dir)

  local fpaths = {}

  local function add(fpath)

    table.insert(fpaths,fpath)

  end

  local function get_files(dir)

    local files = paths.dir(dir)

    for i=1,#files do

      if files[i] ~= '.' and files[i] ~= '..' then

        next_dir = dir..'/'..files[i]

        if isdir(next_dir) then

          get_files(next_dir)

        else

          add(files[i])

        end

      end

    end

  end

  return fpaths

end

On Wed, Feb 22, 2017 at 5:50 AM, Dirk Laurie <dirk.laurie@gmail.com> wrote:

2017年02月22日 2:36 GMT+02:00 p. shkadzko <p.shkadzko@gmail.com>:
> Hi guys,
>
> Here is a function that finds all files in nested dirs and returns a table
> of file paths. I can't figure out how to keep the table variable inside the
> function. For example.
>
> require 'paths'
> require 'lfs'
>
> fpaths = {}
>
> function isdir(path)
>   return lfs.attributes(path)["mode"] == "directory"
> end
>
> function listfiles(dir)
>   local files = paths.dir(dir)
>   for i=1,#files do
>     if files[i] ~= '.' and files[i] ~= '..' then
>       next_dir = dir..'/'..files[i]
>       if isdir(next_dir) then
>         listfiles(next_dir)
>       else
>         table.insert(fpaths,files[i])
>       end
>     end
>   end
>   return fpaths
> end
>
> If I include fpaths inside listfiles it will be overwritten with each new
> recursive call. I tried to create a closure but I think I just do not
> understand how they work in lua.
> Can somebody help me out with this?

A closure is simply a function with some upvalues captured as
they were at the point when the closure was made. E.g. the idiom
for collecting pattern matches into a table:

   do
local tbl = {};
function fct(x) table.insert(tbl,x)
end
function report()
  return #tbl .. " words have been counted so far"
end
   end

("the quick brown fox jumps over the lazy dog"):gsub("%S+",fct)
print(report())
("how much wood would a woodchuck chuck if a woodchuck could chuck
wood"):gsub("%S+",fct)
print(report())

The point is that 'tbl' is still a local variable. You are not creating 'tbl'
in the global namespace as you currently do wuth 'fpaths'. Only 'fct'
and 'report' are global. 'tbl' remains private inside the do block.