Folks,
Just a quick one.
md = /…*?$/.match "dotslash.tar.gz"
md[0] # -> “.tar.gz”
I expect md[0] to be “.gz”, because the question-mark in the regex tells *
not to be greedy. Can anyone enlighten?
Thanks,
Gavin
Hello –
Folks,
Just a quick one.
md = /..*?$/.match “dotslash.tar.gz”
md[0] # → “.tar.gz”I expect md[0] to be “.gz”, because the question-mark in the regex tells *
not to be greedy. Can anyone enlighten?
It will still find the first ‘.’ from the left, and then be
non-greedy. In other words, non-greediness affects how much gets
consumed to the right in a given match.
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
David
···
On Mon, 5 Aug 2002, Gavin Sinclair wrote:
–
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web: http://pirate.shu.edu/~blackdav
Hi!
md = /..*?$/.match “dotslash.tar.gz”
md[0] # → “.tar.gz”I expect md[0] to be “.gz”, because the question-mark in the regex tells *
not to be greedy. Can anyone enlighten?
I think this happens because of leftmost matching.
“.tar.gz” is the least greedy leftmost (even though not the smallest match
at all) match.
Regards,
Bernhard
or this:
/\w+$/
···
On Mon, Aug 05, 2002 at 11:37:12AM +0900, David Alan Black wrote:
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
–
Jim Freeze
If only I had something clever to say for my comment…
~
Hi,
···
At Mon, 5 Aug 2002 11:37:12 +0900, David Alan Black wrote:
Try this:
/.[^.]*$/
Or
str = “dotslash.tar.gz”
if md = str.rindex(/..*$/) #=> 12
str[md…-1] #=> “.gz”
–
Nobu Nakada
Hi –
···
On Mon, 5 Aug 2002, Jim Freeze wrote:
On Mon, Aug 05, 2002 at 11:37:12AM +0900, David Alan Black wrote:
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
or this:
/\w+$/
(You forgot the . 
\w will cover the example given, though I was
generalizing a bit: matching the post-last-dot part of any line.
David
–
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web: http://pirate.shu.edu/~blackdav
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
or this:
/\w+$/
Hmm… that’ll do! Thanks.
···
On Mon, Aug 05, 2002 at 11:37:12AM +0900, David Alan Black wrote:
–
Jim Freeze
If only I had something clever to say for my comment…
~
Note that /\w+$/ will not match all extensions. E.g.,
fred.my-dashed-ext
will return ext.
David replied with my first (unpoosted) attempt.
To be sure you get everything past that last ‘.’, use:
/.([^.]*)$/.match(file)[1]
Jim
···
On Mon, Aug 05, 2002 at 12:57:30PM +0900, Gavin Sinclair wrote:
On Mon, Aug 05, 2002 at 11:37:12AM +0900, David Alan Black wrote:
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
or this:
/\w+$/
Hmm… that’ll do!
–
Jim Freeze
If only I had something clever to say for my comment…
~
Hi –
···
On Mon, 5 Aug 2002, Jim Freeze wrote:
On Mon, Aug 05, 2002 at 12:57:30PM +0900, Gavin Sinclair wrote:
On Mon, Aug 05, 2002 at 11:37:12AM +0900, David Alan Black wrote:
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
or this:
/\w+$/
Hmm… that’ll do!
Note that /\w+$/ will not match all extensions. E.g.,
fred.my-dashed-ext
will return ext.
David replied with my first (unpoosted) attempt.
To be sure you get everything past that last ‘.’, use:/.([^.]*)$/.match(file)[1]
I guess Gavin didn’t need to include the ‘.’ itself in the match (it
was there in the first one, but if /\w+$/ works on his example then it
must not be needed). If it’s not needed one could just do:
/[^.]*$/.match(file)[0]
David
–
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web: http://pirate.shu.edu/~blackdav
David Alan Black wrote:
Hi –
Try this:
/.[^.]*$/
which forces the match to start at the right-most ‘.’ on the line.
or this:
/\w+$/
Hmm… that’ll do!
Note that /\w+$/ will not match all extensions. E.g.,
fred.my-dashed-ext
will return ext.
David replied with my first (unpoosted) attempt.
To be sure you get everything past that last ‘.’, use:/.([^.]*)$/.match(file)[1]
I guess Gavin didn’t need to include the ‘.’ itself in the match (it
was there in the first one, but if /\w+$/ works on his example then it
must not be needed). If it’s not needed one could just do:/[^.]*$/.match(file)[0]
Now wouldn’t all this be much simpler if we had a method
along the lines of ‘basename’, which would pull off the
extension (or suffix) for us? We already have File::basename
and File::dirname, so why not a File::last-part-of-the-name-name?
Or what about a ‘File::parts’ which returns an array of:
directory (or nil), root name (or nil), suffix(es) (or nil).
Would that be more Ruby-esqe?
···
On Mon, 5 Aug 2002, Jim Freeze wrote:
On Mon, Aug 05, 2002 at 12:57:30PM +0900, Gavin Sinclair wrote:
On Mon, Aug 05, 2002 at 11:37:12AM +0900, David Alan Black wrote:
–
Mike Hall
http://www.enteract.com/~mghall
Hi –
···
On Mon, 5 Aug 2002, Mike Hall wrote:
David Alan Black wrote:
/[^.]*$/.match(file)[0]
Now wouldn’t all this be much simpler if we had a method
along the lines of ‘basename’, which would pull off the
extension (or suffix) for us? We already have File::basename
and File::dirname, so why not a File::last-part-of-the-name-name?Or what about a ‘File::parts’ which returns an array of:
directory (or nil), root name (or nil), suffix(es) (or nil).
Would that be more Ruby-esqe?
Heavens – object-oriented regular expressions are Ruby-esque enough
for you?
Of course, writing add-on libraries is very Ruby-esque too, so have
at it!
David
–
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web: http://pirate.shu.edu/~blackdav
[All sorts of people wrote all sorts of things, and then…]
/[^.]*$/.match(file)[0]
Now wouldn’t all this be much simpler if we had a method
along the lines of ‘basename’, which would pull off the
extension (or suffix) for us? We already have File::basename
and File::dirname, so why not a File::last-part-of-the-name-name?Or what about a ‘File::parts’ which returns an array of:
directory (or nil), root name (or nil), suffix(es) (or nil).
Would that be more Ruby-esqe?
I agree there’s room for some help from the File module here. We already
have
File.split(“/home/fred/aliases.sh”) # → [“/home/fred”, “aliases.sh”]
which is nice. I think the most sensible think is for this method to take
an optional parameter, indicating whether the extension should be a separate
element. In fact, it could be an integer specifying how many dots to
include in the extension. So:
File.split(“tuesday.txt”) # → [“.”, “tuesday.txt”]
File.split(“/games/doom.tar.gz”) # → [“/games”, “doom.tar.gz”]
File.split(“/games/doom.tar.gz”, 1) # → [“/games”, “doom.tar”, “gz”]
File.split(“/games/doom.tar.gz”, 2) # → [“/games”, “doom”, “tar.gz”]
File.split(“/games/doom.tar.gz”, 3) # → [“/games”, “doom”, “tar.gz”]
Note that the first two lines represent current File.split behaviour, and
the final three are proposed extensions. The method “split” is very
appropriate here, as (and I should have thought of this earlier)
String.split can be used to chop up a filename into extensions in this
manner.
Of course, we’d need File.extension(path, n=1) to match File.dirname and
File.basename, as well.
–Gavin
···
----- Original Message -----
From: “Mike Hall” mghall@enteract.com
sub(/are/, “aren’t”) #
David
···
On Tue, 6 Aug 2002, David Alan Black wrote:
Hi –
On Mon, 5 Aug 2002, Mike Hall wrote:
David Alan Black wrote:
/[^.]*$/.match(file)[0]
Now wouldn’t all this be much simpler if we had a method
along the lines of ‘basename’, which would pull off the
extension (or suffix) for us? We already have File::basename
and File::dirname, so why not a File::last-part-of-the-name-name?Or what about a ‘File::parts’ which returns an array of:
directory (or nil), root name (or nil), suffix(es) (or nil).
Would that be more Ruby-esqe?Heavens – object-oriented regular expressions are Ruby-esque enough
for you?
–
David Alan Black
home: dblack@candle.superlink.net
work: blackdav@shu.edu
Web: http://pirate.shu.edu/~blackdav