[Ruby] Grep with Ruby
ruby -ne 'puts $_ if $_ =~ /text/' *
-n places an implicit while gets ... end block
gets(separator=$/) => string or nil
------------------------------------------------------------------------
Returns (and assigns to +$_+) the next line from the list of files
in +ARGV+ (or +$*+), or from standard input if no files are present
on the command line. Returns +nil+ at end of file. The optional
argument specifies the record separator. The separator is included
with the contents of each record. A separator of +nil+ reads the
entire contents, and a zero-length separator reads the input one
paragraph at a time, where paragraphs are divided by two
consecutive newlines. If multiple filenames are present in +ARGV+,
+gets(nil)+ will read the contents one file at a time.
ARGV << "testfile"
print while gets
_produces:_
This is line one
This is line two
This is line three
And so on...
The style of programming using +$_+ as an implicit parameter is
gradually losing favor in the Ruby community.
