Array.each puzzle from new ruby-er

Given:
lines = file.readlines("\x15") # don’t ask :slight_smile:
lines.each do |y|
y.chomp!("\x15")
y.sub!(/^\n/,"") #kill off the extra line feeds
if y =~ /^***/ then
y = “” + y + “”

[ assume ends]
puts lines

my output for the affected elements is:

value of y

How can I get the results to be
value of y

I’ve tried changing y to y.to_s; I still get the new line.

I’m sure this is obvious if you know what you’re doing, but I’m stumped.
Can somebody give me a clue?

TIA if you take a moment to point me in the right direction.
Gani

On 8/7/07, Gani R. [email protected] wrote:

puts lines
I’m sure this is obvious if you know what you’re doing, but I’m stumped.
Can somebody give me a clue?

TIA if you take a moment to point me in the right direction.
Gani

Posted via http://www.ruby-forum.com/.

Hi Gani,

try
y.gsub!(/^\n/,“”) #kill off the extra line feeds
instead of
y.sub!(/^\n/,“”) #kill off the extra line feeds

Ron

Gani R. wrote:

Given:
lines = file.readlines("\x15") # don’t ask :slight_smile:
lines.each do |y|
y.chomp!("\x15")
y.sub!(/^\n/,"") #kill off the extra line feeds
I would think it better to just call y.chomp! here (with no argument).

if y =~ /^\*\*\*/ then
  y = "<someTag>" + y + "</someTag>"

Know that this is actually rebinding the local variable y to point to a
new object, not modifying the old object. If your goal was to modify the
array “lines”, you should change “lines.each” to “lines.map” and make
sure you end the block with a statement that returns the modified y.

perhaps:
lines.map do |y|
y = y.chomp("\x15").chomp
y = “” + y + “” if y =~ /^***/
y
end

Dan

On 8/7/07, ronald braswell [email protected] wrote:

if y =~ /^\*\*\*/ then

value of y
Posted via http://www.ruby-forum.com/.

Oops. That would not be any different because of the ^anchor.
y.sub!(/^\n+/,“”) might do the trick.

Ron

Know that this is actually rebinding the local variable y to point to a
new object, not modifying the old object. If your goal was to modify the
array “lines”, you should change “lines.each” to “lines.map” and make
sure you end the block with a statement that returns the modified y.

perhaps:
lines.map do |y|
y = y.chomp("\x15").chomp
y = “” + y + “” if y =~ /^***/
y
end

Dan

Sorry, actually doing each_with_index do |y,ind| (etc) and specifically
setting lines[ind] = y
but my original question remains: how do i make the “” + y leave
off the \n so the output is
text of y
Thanks again

Gani R. wrote:

end

Dan

Sorry, actually doing each_with_index do |y,ind| (etc) and specifically
setting lines[ind] = y
but my original question remains: how do i make the “” + y leave
off the \n so the output is
text of y
Thanks again

Sorry, I thought that would work but didn’t test it. “y.lstrip” will do
what you want, but will also will strip leading whitespace, which might
not be okay. If not, “y[1…-1]” should suffice–this will return y from
the second character on.
y = y[1…-1] if y =~ /^\n/

Dan

On Aug 7, 2:04 pm, Gani R. [email protected] wrote:

end
Posted viahttp://www.ruby-forum.com/.
Have you considered switching to map?

As for debugging, I’d try tracking it down using p

lines = file.readlines(“\x15”).map do |line|
line.chomp!(“\x15”)
line.sub!(/^\n/, “”)
line = “” + line + “” if line =~ /^*{3}/
p [:line, line] # comment me out after debugging
line
end

p [:lines, lines] # comment me out after debugging

puts lines

Noah E. wrote:

On Aug 7, 2:04 pm, Gani R. [email protected] wrote:

end
Posted viahttp://www.ruby-forum.com/.
Have you considered switching to map?

As for debugging, I’d try tracking it down using p

lines = file.readlines(“\x15”).map do |line|
line.chomp!(“\x15”)
line.sub!(/^\n/, “”)
line = “” + line + “” if line =~ /^*{3}/
p [:line, line] # comment me out after debugging
line
end

p [:lines, lines] # comment me out after debugging

puts lines

Oh. I did a subset of the p [:line, line] and it looks like i had some
\n and some \r\n occurring. I was just pulling the \r\n on my sub call
(wrote it as \n to simplify)because when I was looking at the original
with end of line showing they all showed as CRLF. Odd.
Much improved output, and another tool in my meager toolkit. Thanks so
much, Noah and all other repliers! I’ll look at replacing the each with
map/collect now that I know about it. I do have the Pragmatic
programming book…
Cheers, Gani

On Aug 7, 9:10 pm, Gani R. [email protected] wrote:

line.sub!(/^\n/, “”)
\n and some \r\n occurring. I was just pulling the \r\n on my sub call
(wrote it as \n to simplify)because when I was looking at the original
with end of line showing they all showed as CRLF. Odd.
Much improved output, and another tool in my meager toolkit. Thanks so
much, Noah and all other repliers! I’ll look at replacing the each with
map/collect now that I know about it. I do have the Pragmatic
programming book…
Cheers, Gani


Posted viahttp://www.ruby-forum.com/.

Piece of advice - concatenation in Ruby is very fast but you should
take the better way by using:
y = “” << y << “”
which is a little faster with same readability :wink: