From: Stefano Crocco <stefano.crocco@...>
Date: 2007-02-24T00:33:16+09:00
Subject: Re: undefined method `at' for nil:NilClass while i use parseexce

Alle venerd狸 23 febbraio 2007, Ruhul Amin ha scritto:
> I use this code to open my '2007-02-231028.xls' file. the file is in the
> same directory of the program.
> my code:
>
> require 'parseexcel'
>
> workbook = Spreadsheet::ParseExcel.parse('2007-02-231028.xls')
>
> worksheet = workbook.worksheet(0)
>
> skip = 2
> worksheet.each(skip) { |row|
> # a row is actually just an Array of Cells..
> first_cell = row.at(0)
>
> }
>
> Error is:
> undefined method `at' for nil:NilClass
>
> I can not understand the error. please help me as i am a niwbie in ruby

The error message simply means that you're calling the method 'at' for an 
object of class NilClass (that is, nil). Since nil doesn't have a at method, 
you get an error. It seems that worksheet.each passes nil to the block, 
instead of an array. I'm not familiar with parseexcel, so I can't tell you 
why it does that. I'd suggest you to check the class of row before using it:

worksheet.each(skip) { |row|
  puts row.class
  first_cell=row.at(0)
}

This may give you an idea about why the block is passed nil instead than an 
array.

I hope this helps

Stefano