CSVobj

Aims

CSVobj has two simple aims in the processing of CSV files:

• clarity

• robustness

It achieves these aims by automatically instantiating a class with dynamic attributes that can be used to refer to each column of the CSV by name. Each attribute name is derived in a predictable fashion from the column headers (the first row of the CSV).

Clarity

Rather than referring programatically to the “third element of the row” (“row”) one can simply say “row.last_name”.

Robustness

Any change to the CSV format (eg by inserting a new column between two existing columns) will not require a program change: you do not need to hunt down all references to “row” and make them “row”; they remain “row.last_name”.

Example

Given the following CSV file:

First Name,Last Name
Cheryl,James
Sandra,Denton
Deidra,Roper

we can extract just the last names as follows:

# Get the gem
require 'rubygems'
require 'csvobj'

# Subclass because #parse defines methods on the class
class MyCsv < CSVobj ; end

# First command line argument is CSV file to read
csv_file = File.new( ARGV[0] )

# Parse the file, print the "last name" column of each row
MyCsv.parse(csv_file).each do |row|
  puts row.last_name
end