Question: formatting strings from array for text files

Ruby
1

I’m not sure who to have an array format correctly when written to a
text file.
Doing something like myarray = [‘five’,‘four’,‘three’,‘two’,‘one’]
works almost correctly but
myarray = [’…/./*.docs’] seems to write them out without linebreaks.

So while I can figure out how to print them nicely using some iterator
to the screen
Using,
File.open filename, ‘w’ do |doc|
doc.write myarray
end
I can’t seem to figure out a way to format the strings correctly.

Stuart

2

2006/7/6, Dark A. [email protected]:

I’m not sure who to have an array format correctly when written to a text file.

What does “correctly” mean?

Doing something like myarray = [‘five’,‘four’,‘three’,‘two’,‘one’]
works almost correctly but
myarray = [‘…/./*.docs’] seems to write them out without linebreaks.

This is not a print statement. What did you do to actually print it?

So while I can figure out how to print them nicely using some iterator
to the screen
Using,
File.open filename, ‘w’ do |doc|
doc.write myarray
end
I can’t seem to figure out a way to format the strings correctly.

Try this:

doc.write myarray.join ", "

Depends on what you mean by “proper output”.

Kind regards

robert

3

I must have not explained myself well.
Right now my file looks like this:

c:/dir1/doc1.docc;/dir1/doc3.docc:/dir1/doc4.docc:/dir1/doc5.doc
…i.e. no line breaks

I want it took look like this:
c:/dir1/doc1.doc
c;/dir1/doc3.doc
c:/dir1/doc4.doc
c:/dir1/doc5.doc
…

Stuart

4

Dark A. wrote:

c:/dir1/doc5.doc

  doc.write myarray

robert

–
Have a look: Robert K. | Flickr

Try using ‘doc.puts’ instead of ‘doc.write’. ‘puts’ will automatically
add line breaks, whereas ‘write’ will not.

-Justin

5

Thank you that was a huge improvement, still battling a few more format
issues:
when I open the file:
It has the 3 hypens as the first line and a hyphen before every file
name. Can’t I get rid of those ?

  • c:/dir1/doc1.doc
  • c:/dir1/doc2.doc
  • c:/dir1/doc3.doc
  • c:/dir1/doc4.doc
  • c:/dir1/doc5.doc
  • c:/dir1/doc6.doc

Stuart

6

I’d think there has to be a way.

7

Okay, I made some changes to my code. I was using .to_yaml, without
it, the extra characters are now gone.

However, I’m writing this file successfully yet Ruby is returning false.
So, perhaps someone would know why ? (btw, went from .docs to .mp3’s)

songs = Dir[‘c:/mp3/*.mp3’]
filename = ‘songs.m3u’

File.open filename, ‘w’ do |f|
f.puts songs
end

readlist = File.read filename

puts(readlist == songs)

Stuart

8

Dark A. wrote:

f.puts songs

  • c:/dir1/doc3.doc

Stuart
[‘five’,‘four’,‘three’,‘two’,‘one’]

Using,
Depends on what you mean by “proper output”.
Try using ‘doc.puts’ instead of ‘doc.write’. ‘puts’ will

You are comparing a string to an array. File.read returns a string. Try
something like:

readlist = File.readlines(filename).map { |line| line.chomp}

File.readlines will return an array with an element for each line. But
they will then have the end-of-line character attached (added when we
wrote the file), so we have to remove those with chomp.

-Justin

9

Dark A. wrote:

  • c:/dir1/doc1.doc
  • c:/dir1/doc2.doc
  • c:/dir1/doc3.doc
  • c:/dir1/doc4.doc
  • c:/dir1/doc5.doc
  • c:/dir1/doc6.doc

How are you building the array? What you are seeing as output must be
what’s in the array, unless you are adding those hyphens at some point.
Maybe do a

p myarray

to see exactly what is in the array.

Of course, you could just do some string parsing and remove the hyphens.

-Justin