Ruby Command Line One Liner


#1

Hi,

I try to write a Ruby one-liner that replaces the header information of
some *.java files.

My first try worked perfect for a single file. But I have no idea on how
to change my one-liner to work with multiple files.

Here is my one-liner for a single file:

ruby -i.bak -p -e ‘puts ARGF.read.gsub(/.*(?=package)/m,"/**\n * foo.bar
2001-2009\n\ **/\n")’ test/Test.java

Does anybody have a idea on how to solve this problem for all *.java
files in the test directory?

Thanks for your answer,
Alain.


#2

Hi –

On Fri, 2 Jan 2009, Alain H. wrote:

ruby -i.bak -p -e ‘puts ARGF.read.gsub(/.*(?=package)/m,"/**\n * foo.bar
2001-2009\n\ **/\n")’ test/Test.java

Does anybody have a idea on how to solve this problem for all *.java
files in the test directory?

The -p flag will do the read/write loop for you, so all you have to do
is something like this:

$ cat abc.txt
hello
$ cat def.txt
goodbye

$ ruby -pi.bak -e ‘$_.upcase!’ abc.txt def.txt

$ cat abc.txt
HELLO
$ cat def.txt
GOODBYE

David


David A. Black / Ruby Power and Light, LLC
Ruby/Rails consulting & training: http://www.rubypal.com
Coming in 2009: The Well-Grounded Rubyist (http://manning.com/black2)

http://www.wishsight.com => Independent, social wishlist management!


#3

On Thu, Jan 1, 2009 at 11:51 AM, Alain H.
removed_email_address@domain.invalid wrote:

I try to write a Ruby one-liner that replaces the header information of
some *.java files.

My first try worked perfect for a single file. But I have no idea on how
to change my one-liner to work with multiple files.

You might be interested in this: http://rush.heroku.com/


#4

Hi –

On Fri, 2 Jan 2009, Alain H. wrote:

$ cat abc.txt
Coming in 2009: The Well-Grounded Rubyist (http://manning.com/black2)
/**
package test;

If I use the one-liner at the top of the message with an input like
‘test/Tes*.java’ then the ARGF stream does somehow not differ between
the different files.

It sounds like you might want -n rather than -p. -n does the same
loop, but without printing. You could arrange to print once you’ve hit
/package/.

David


David A. Black / Ruby Power and Light, LLC
Ruby/Rails consulting & training: http://www.rubypal.com
Coming in 2009: The Well-Grounded Rubyist (http://manning.com/black2)

http://www.wishsight.com => Independent, social wishlist management!


#5

David A. Black wrote:

Hi –

On Fri, 2 Jan 2009, Alain H. wrote:

ruby -i.bak -p -e ‘puts ARGF.read.gsub(/.*(?=package)/m,"/**\n * foo.bar
2001-2009\n\ **/\n")’ test/Test.java

Does anybody have a idea on how to solve this problem for all *.java
files in the test directory?

The -p flag will do the read/write loop for you, so all you have to do
is something like this:

$ cat abc.txt
hello
$ cat def.txt
goodbye

$ ruby -pi.bak -e ‘$_.upcase!’ abc.txt def.txt

$ cat abc.txt
HELLO
$ cat def.txt
GOODBYE

David


David A. Black / Ruby Power and Light, LLC
Ruby/Rails consulting & training: http://www.rubypal.com
Coming in 2009: The Well-Grounded Rubyist (http://manning.com/black2)

http://www.wishsight.com => Independent, social wishlist management!

Thanks a lot for your answer.

The problem of the -p flag is, that the input stream is read line by
line. Then the regex /.*(?=package)/ will only be applied to one line.
But I want to remove all lines before the line starting with “package”.
See the following example:

/**

  • header
    **/
    package test;

The result of the replacement looks like this:

/**

  • foo.bar
    **/
    package test;

If I use the one-liner at the top of the message with an input like
‘test/Tes*.java’ then the ARGF stream does somehow not differ between
the different files.

Best regards, Alain.


#6

On Jan 1, 1:51 pm, Alain H. removed_email_address@domain.invalid wrote:

ruby -i.bak -p -e ‘puts ARGF.read.gsub(/.*(?=package)/m,"/**\n * foo.bar
2001-2009\n\ **/\n")’ test/Test.java

Does anybody have a idea on how to solve this problem for all *.java
files in the test directory?

Thanks for your answer,
Alain.

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

ruby -i.bak -0777 -pe"sub /.*foo/m,‘bar’" *.java


#7

unknown wrote:

On Jan 1, 1:51�pm, Alain H. removed_email_address@domain.invalid wrote:

ruby -i.bak -p -e ‘puts ARGF.read.gsub(/.*(?=package)/m,"/**\n * foo.bar
2001-2009\n\ **/\n")’ test/Test.java

Does anybody have a idea on how to solve this problem for all *.java
files in the test directory?

Thanks for your answer,
Alain.

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

ruby -i.bak -0777 -pe"sub /.*foo/m,‘bar’" *.java

Thanks a lot for the help.

The -0777 flag was the key to success, Alain.