Ruby save Excel as CSV - ruby

Question

I am trying to go through each .xls file in a directory and save a .csv for each file. I am working with the 'roo' gem and am seeing some errors. Totally open to other approaches, I just need to keep this in Ruby without moving to Ruby on Rails. I am running Ruby 1.9.2 and executing in terminal on a Mac.
Code so far:
#! /usr/bin/ruby
require 'roo'
# change excel files to csv
begin
Dir["/tmp/*.xls"].each do |file|
file_path = "#{file}"
file_basename = File.basename(file, ".xls")
xls = Excel.new(file_path)
xls.to_csv = ("/tmp/#{file_basename}.csv")
end
end
And here is the error I get: (line numbers are not the same as example, line 27 is begin statement)
/Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/roo-1.10.1/lib/roo/excel.rb:284:in `platform_specific_iconv': uninitialized constant Excel::Iconv (NameError)
from /Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/roo-1.10.1/lib/roo/excel.rb:277:in `normalize_string'
from /Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/roo-1.10.1/lib/roo/excel.rb:139:in `block in sheets'
from /Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/roo-1.10.1/lib/roo/excel.rb:139:in `collect'
from /Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/roo-1.10.1/lib/roo/excel.rb:139:in `sheets'
from /Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/roo-1.10.1/lib/roo/excel.rb:123:in `initialize'
from excel_conversion_test.rb:32:in `new'
from excel_conversion_test.rb:32:in `block in <main>'
from excel_conversion_test.rb:28:in `each'
from excel_conversion_test.rb:28:in `<main>'
As suggested I tried to install inconv and got the following errors:
ERROR: Error installing iconv:
ERROR: Failed to build gem native extension.
/Users/pierce/.rbenv/versions/1.9.2-p290/bin/ruby extconf.rb
checking for iconv() in iconv.h... no
checking for iconv() in -liconv... yes
checking for const of iconv() 2nd argument... no
creating Makefile
make
/usr/bin/gcc-4.2 -I. -I/Users/pierce/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/x86_64-darwin11.2.0 -I/Users/pierce/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/ruby/backward -I/Users/pierce/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1 -I. -I'/Users/pierce/.rbenv/versions/1.9.2-p290/include' -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -fno-common -O3 -ggdb -Wextra -Wno-unused-parameter -Wno-parentheses -Wpointer-arith -Wwrite-strings -Wno-missing-field-initializers -Wshorten-64-to-32 -Wno-long-long -pipe -o iconv.o -c iconv.c
In file included from iconv.c:21:
/Users/pierce/.rbenv/versions/1.9.2-p290/include/ruby-1.9.1/ruby/backward/st.h:2:2: warning: #warning use "ruby/st.h" instead of bare "st.h"
iconv.c:22:20: error: intern.h: No such file or directory
iconv.c: In function ‘map_charset’:
iconv.c:139: error: ‘struct RHash’ has no member named ‘tbl’
iconv.c:139: error: ‘struct RHash’ has no member named ‘tbl’
iconv.c:142: error: ‘struct RHash’ has no member named ‘tbl’
iconv.c: In function ‘iconv_create’:
iconv.c:187: error: ‘struct RString’ has no member named ‘len’
iconv.c:188: error: ‘struct RString’ has no member named ‘len’
iconv.c:190: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:190: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:190: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:190: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:192: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:193: error: ‘struct RString’ has no member named ‘len’
iconv.c: In function ‘iconv_fail’:
iconv.c:328: error: ‘struct RString’ has no member named ‘len’
iconv.c: In function ‘iconv_fail_retry’:
iconv.c:352: error: ‘ruby_errinfo’ undeclared (first use in this function)
iconv.c:352: error: (Each undeclared identifier is reported only once
iconv.c:352: error: for each function it appears in.)
iconv.c: In function ‘rb_str_derive’:
iconv.c:371: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:371: error: ‘struct RString’ has no member named ‘len’
iconv.c:373: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:373: error: ‘struct RString’ has no member named ‘len’
iconv.c:374: error: ‘struct RString’ has no member named ‘ptr’
iconv.c: In function ‘iconv_convert’:
iconv.c:418: error: ‘struct RArray’ has no member named ‘len’
iconv.c:418: error: ‘struct RArray’ has no member named ‘ptr’
iconv.c:436: error: ‘struct RString’ has no member named ‘len’
iconv.c:437: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:455: warning: comparison of unsigned expression >= 0 is always true
iconv.c:458: warning: comparison between signed and unsigned
iconv.c:459: warning: comparison between signed and unsigned
iconv.c:491: warning: implicit conversion shortens 64-bit value into a 32-bit value
iconv.c:494: warning: implicit conversion shortens 64-bit value into a 32-bit value
iconv.c:497: error: ‘struct RArray’ has no member named ‘len’
iconv.c:498: error: ‘struct RArray’ has no member named ‘ptr’
iconv.c:499: error: ‘struct RArray’ has no member named ‘ptr’
iconv.c:501: error: ‘struct RString’ has no member named ‘len’
iconv.c:502: error: ‘struct RString’ has no member named ‘ptr’
iconv.c:514: warning: implicit conversion shortens 64-bit value into a 32-bit value
iconv.c: In function ‘iconv_s_convert’:
iconv.c:615: error: ‘struct RString’ has no member named ‘len’
make: *** [iconv.o] Error 1
Gem files will remain installed in /Users/pierce/.rbenv/versions/1.9.2-p290/lib/ruby/gems/1.9.1/gems/iconv-0.1 for inspection.

Answer 1

Add this: require 'iconv' before require 'roo'. I found this solution here, and i got there using this query on google: roo/excel.rb:284. An example here! Notice about the = in this line: xls.to_csv = ("/tmp/#{file_basename}.csv") that should not be there.

Answer 2

I decided to post an answer to try and explain this situation for anyone else that arrives here from Google.
As David points out, to fix this error...
uninitialized constant Excel::Iconv
...you'll have to require "iconv":
require "iconv"
require "roo"
This is because the Roo gem calls Iconv.new in its internal Excel class but Roo forgot to require "iconv" itself, so you're forced to do it. It's a bug. It's no different than calling Set.new without require "set"
Iconv is part of Ruby 1.8 and 1.9's standard library. You don't install it. It's already there.
However, it's worth pointing out that Iconv is deprecated in Ruby 1.9 and removed in Ruby 2.0.