From: pjb@... (Pascal J. Bourguignon)
Date: 2009-06-15T23:00:11+09:00
Subject: Re: formatting a listing

George George <george.githinji@gmail.com> writes:

> (printf "%s\n\n" ,
>  (begin
>     (matrix = (Array.new))
>     (ncols = 1)
>     (matrix.push(Array.new))
>     (((IO.readlines'/home/george/test.data').
>       map { | line | (line.strip) }).
>      each { | item | (if (item == "")
>                         (ncols = (ncols + 1))
>                         (matrix.push(Array.new))
>                       else
>                         ((matrix.at(ncols - 1)).push item)
>                       end)
>      })
>     (height = ((matrix.map { | column | (column.size) }).max))
>     (widths = (matrix.map { | column | ((column.map { | cell |
> ((sprintf("%s" , cell)).size) }).max) }))
>     ((((matrix.map { | column | (column + (Array.new((height -
> (column.size)) , ""))) }) .
>        transpose).
>       map { | row | ((([ row , widths ].transpose).
>                       map { | r , w | (sprintf( "%*s" , w , r)) }) .
>                      join ",")}).
>      join "\n")
>   end))
>
> produces an error:
> in `sprintf': no implicit conversion from nil to integer (TypeError)


Well, I tried it with this file:
-----
1
2
3

3
4
5

20
3
5
5

-----

You may try to execute it expression per expression, and see where that nil comes from?


irb(main):850:0> 
(matrix = (Array . new))
[]
irb(main):856:0> 
(ncols = 1)
1
irb(main):862:0> 
(matrix . push(Array . new))
[[]]
irb(main):868:0> 
(((IO . readlines'/tmp/test.data') . 
      map { | line | (line . strip) }) .
     each { | item | (if (item == "")
                        (ncols = (ncols + 1))
                        (matrix . push(Array . new))
                      else
                        ((matrix . at(ncols - 1)) . push item)
                      end)
     })
["1", "2", "3", "", "3", "4", "5", "", "20", "3", "5", "5"]
irb(main):890:0> 
(height = ((matrix . map { | column | (column . size) }) . max))
4
irb(main):896:0> 
(widths = (matrix . map { | column | ((column . map { | cell | ((sprintf("%s" , cell)) . size) }) . max) }))
[1, 1, 2]
irb(main):902:0> 
((((matrix . map { | column | (column + (Array . new((height - (column . size)) , ""))) }) . 
       transpose) .
      map { | row | ((([ row , widths ] . transpose) . 
                      map { | r , w | (sprintf( "%*s" , w , r)) }) .
                     join ",")}) . 
     join "\n")
"1,3,20\n2,4, 3\n3,5, 5\n , , 5"
irb(main):918:0> 
(begin
    (matrix = (Array . new))
    (ncols = 1)
    (matrix . push(Array . new))
    (((IO . readlines'/tmp/test.data') . 
      map { | line | (line . strip) }) .
     each { | item | (if (item == "")
                        (ncols = (ncols + 1))
                        (matrix . push(Array . new))
                      else
                        ((matrix . at(ncols - 1)) . push item)
                      end)
     })
    (height = ((matrix . map { | column | (column . size) }) . max))
    (widths = (matrix . map { | column | ((column . map { | cell | ((sprintf("%s" , cell)) . size) }) . max) }))
    matrix
    ((((matrix . map { | column | (column + (Array . new((height - (column . size)) , ""))) }) . 
       transpose) .
      map { | row | ((([ row , widths ] . transpose) . 
                      map { | r , w | (sprintf( "%*s" , w , r)) }) .
                     join ",")}) . 
     join "\n")
  end)
"1,3,20\n2,4, 3\n3,5, 5\n , , 5"
irb(main):968:0> 
(matrix = (Array . new))
[]
irb(main):974:0> 
(ncols = 1)
1
irb(main):980:0> 
(matrix . push(Array . new))
[[]]
irb(main):986:0> 
(((IO . readlines'/tmp/test.data') . 
      map { | line | (line . strip) }) .
     each { | item | (if (item == "")
                        (ncols = (ncols + 1))
                        (matrix . push(Array . new))
                      else
                        ((matrix . at(ncols - 1)) . push item)
                      end)
     })
["1", "2", "3", "", "3", "4", "5", "", "20", "3", "5", "5"]
irb(main):1005:0> 
matrix
[["1", "2", "3"], ["3", "4", "5"], ["20", "3", "5", "5"]]
irb(main):1008:0> 
(height = ((matrix . map { | column | (column . size) }) . max))
4
irb(main):1014:0> 
(widths = (matrix . map { | column | ((column . map { | cell | ((sprintf("%s" , cell)) . size) }) . max) }))
[1, 1, 2]
irb(main):1020:0> 
matrix
[["1", "2", "3"], ["3", "4", "5"], ["20", "3", "5", "5"]]
irb(main):1026:0> 
((((matrix . map { | column | (column + (Array . new((height - (column . size)) , ""))) }) . 
       transpose) .
      map { | row | ((([ row , widths ] . transpose) . 
                      map { | r , w | (sprintf( "%*s" , w , r)) }) .
                     join ",")}) . 
     join "\n")
"1,3,20\n2,4, 3\n3,5, 5\n , , 5"
irb(main):1042:0> 

-- 
__Pascal Bourguignon__