>>>>> "PJ" == Paul Johnson <p...@pjcj.net> writes:
PJ> On Sun, May 15, 2011 at 01:31:47PM -0400, Jim Green wrote:
>> this is very nice, don't need to call perl in perl anymore..
>>
>> perl -pi -e '$_ = "" if /foo/' filename
>>
>> but what if the file is very large? slurping the file in to memory will
>> be ok?
>>
>> or is there any other alternatives you are aware of? or you can dismiss?
PJ> {
PJ> local ($^I, @ARGV) = ("", "filename");
PJ> while (<>)
PJ> {
PJ> print unless /foo/;
PJ> }
PJ> }
PJ> is the idiomatic way to do that. Well, to do:
and also very slow and also clunky. as i said, you need to localize
those vars and also not be using <> elsewhere. it is just a bad idiom
and now it can be laid to rest. :)
PJ> perl -ni -e 'print unless /foo/' filename
about the same as my version. i wanted to show how you would do the same
logic with both -pi and edit_file_lines. my sub doesn't have a print
command so you can invert the logic which is why i used -p and not -n.
PJ> which is the idiomatic way to do what you had written. For a more
PJ> direct translation, substitute the loop contents with
PJ> $_ = "" if /foo/;
PJ> print;
and you don't need the print if you use -p.
uri
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