Strip is not stripping trailing whitespace

[Taylor Strait]

I have files with city names which have one or two trailing whitespaces:

Adelanto <-
Agoura Hills <-
Alameda <-
Albany <-
Alhambra <-
Aliso Viejo <-

My method just iterates and strips!

def trim(state)
diskfile = File.new(state + "-cleaned.txt", "w")
$stdout = diskfile

IO.foreach(state + ".txt") do |line|
line.strip!
puts line
end

diskfile.close
$stdout = STDOUT
end

The output successfully removes leading whitespace but not trailing
whitespace. What am I doing wrong? I would chop! but the number of
trailing whitespace characters varies and my attempt at a while loop to
check and chop! was unsuccessful.

 

[William James]

I have files with city names which have one or two trailing whitespaces:

Adelanto <-
Agoura Hills <-
Alameda <-
Albany <-
Alhambra <-
Aliso Viejo <-

My method just iterates and strips!

def trim(state)
diskfile = File.new(state + "-cleaned.txt", "w")
$stdout = diskfile

IO.foreach(state + ".txt") do |line|
line.strip!
puts line
end

diskfile.close
$stdout = STDOUT
end

The output successfully removes leading whitespace but not trailing
whitespace. What am I doing wrong? I would chop! but the number of
trailing whitespace characters varies and my attempt at a while loop to
check and chop! was unsuccessful.

Perhaps there are some control characters at the lines' ends.

The way that you're writing to a file seems roundabout
and peculiar to me.

def trim(state)
open(state + "-cleaned.txt", "w") do |out|
IO.foreach(state + ".txt") do |line|
# The next line will show control characters.
p line
out.puts line.strip
end
end
end

 

[Morton Goldberg]

I have files with city names which have one or two trailing
whitespaces:

Adelanto <-
Agoura Hills <-
Alameda <-
Albany <-
Alhambra <-
Aliso Viejo <-

My method just iterates and strips!

def trim(state)
diskfile = File.new(state + "-cleaned.txt", "w")
$stdout = diskfile

IO.foreach(state + ".txt") do |line|
line.strip!
puts line
end

diskfile.close
$stdout = STDOUT
end

The output successfully removes leading whitespace but not trailing
whitespace. What am I doing wrong? I would chop! but the number of
trailing whitespace characters varies and my attempt at a while
loop to
check and chop! was unsuccessful.

Strip is working as it should. Your input lines don't end is spaces,
but with a line end code. The easy way to do what you want is
something like the following:

<code>
#! /usr/bin/env ruby -w

PREFOX = "/Users/mg/Desktop/test"
SUFFIX = ".txt"
File.open(PREFOX + "-cleaned" + SUFFIX, "w") do |out_file|
File.open(PREFOX + SUFFIX) do |in_file|
in_file.each { |line| out_file.puts line.chomp.strip }
end
end
</code>

Note the use of String#chomp. Also, I'm recommending that you use
File.open and that you don't mess with $stdout. File#open
automatically takes care of closing the files it opens.

Regards, Morton

 

[Taylor Strait]

def trim(state)
open(state + "-cleaned.txt", "w") do |out|
IO.foreach(state + ".txt") do |line|
# The next line will show control characters.
p line
out.puts line.strip
end
end
end

outputs:

"Yorba Linda\240\240\n"
"Yountville \n"
"Yreka\240\240\n"
"Yuba City\240\240\n"
"Yucaipa\240\240\n"
"Yucca Valley "
=> nil

but alas the generated file still has trailing whitespaces. What should
I do to remove the \240 and \n? Is that not what strip! does?

 

[Taylor Strait]

Note the use of String#chomp

Thanks, Morton. That was the key. I just appended two .chomp methods
and it fixed it right up. I appreciate everyone's help!

 

[William James]

Thanks, Morton. That was the key. I just appended two .chomp methods
and it fixed it right up.

It couldn't have.

strip removes newlines, because they are whitespace.
On the other hand, neither chomp nor strip removes "\240".
=> "foo \240"

 

[Taylor Strait]

It couldn't have.

strip removes newlines, because they are whitespace.
On the other hand, neither chomp nor strip removes "\240".

=> "foo \240"

This is why I shouldn't code at 3:30am! I had used chop instead, which
of course truncated the text in rare cases. How can I remove \240?

 

[Eric Hodel]

This is why I shouldn't code at 3:30am! I had used chop instead,
which
of course truncated the text in rare cases. How can I remove \240?

String#gsub

line.gsub(/[\240]/, '')

 

[Taylor Strait]

How can I remove \240?

Time for a break. The answer is: delete(0240.chr)

 

[Carlos]

This is why I shouldn't code at 3:30am! I had used chop instead, which
of course truncated the text in rare cases. How can I remove \240?

line.delete! "\240"

or, if you want to delete them at the end only,

line.sub! /\240+$/, ""

Good luck.

--

 

[William James]

This is why I shouldn't code at 3:30am! I had used chop instead, which
of course truncated the text in rare cases. How can I remove \240?

Remove ASCII 128-- 255 at end of line:

irb(main):016:0> "foo\240\250 \n".strip.
irb(main):017:0* sub(/[#{128.chr}-#{255.chr}]+$/,"")
=> "foo"

 

[Robert Klemme]

This is why I shouldn't code at 3:30am! I had used chop instead, which
of course truncated the text in rare cases. How can I remove \240?

Remove ASCII 128-- 255 at end of line:

irb(main):016:0> "foo\240\250 \n".strip.
irb(main):017:0* sub(/[#{128.chr}-#{255.chr}]+$/,"")
=> "foo"

Why not combine them like this:

irb(main):007:0> s="foo\240\250 \n"
=> "foo\240\250 \n"

irb(main):015:0> s.sub /[\200-\377\s]+$/, ''
=> "foo"

Cheers

robert

 

[Charles A Gray]

This is why I shouldn't code at 3:30am! I had used chop instead,
which
of course truncated the text in rare cases. How can I remove \240?

String#gsub

line.gsub(/[\240]/, '')

line.chop will remove one of the "\240"s. line.chop.chop.chop will
remove all three, but they will still be on line. To completely remove
them, use line.chop!.chop!.chop! where line = the string you wish to
change.

 

[Chris Gernon]

line.chop will remove one of the "\240"s. line.chop.chop.chop will
remove all three, but they will still be on line. To completely remove
them, use line.chop!.chop!.chop! where line = the string you wish to
change.

line = line.chop.chop.chop would be better. In general, you shouldn't
chain destructive methods, because they usually return nil when they
fail:

irb> line = ''
=> ""
irb> line.chop!
=> nil
irb> line = ''
=> ""
irb(main):004:0> line.chop!chop!
TypeError: $_ value need to be String (nil given)
from (irb):4:in `chop!'
from (irb):4

As opposed to:

irb> line = ''
=> ""
irb> line = line.chop.chop.chop
=> ""