zsh-users
 help / Atom feed
* is there a way to use *.{txt,zip,tbz,dmg} if one or more might be missing?
@ 2019-07-07 23:27 TJ Luoma
  2019-07-08  0:10 ` Bart Schaefer
  0 siblings, 1 reply; 4+ messages in thread
From: TJ Luoma @ 2019-07-07 23:27 UTC (permalink / raw)
  To: zsh-users

This seems like one of those things that I might have not learned that
everyone else knows, so I thought I'd ask.

I can use this:

        mv -vn *.{txt,zip,tbz,dmg} ~/dir/

to move all files that end with zip/txt/tbz/dmg to ~/dir/

BUT it will fail if it does not find at least one file with each of
those extensions.

Is there a way to do basically the same thing, but tell `mv` "if is at
least one file with any of these extensions, then move to ~/dir/" ?

I suppose I could use `find` with various `-o` flags, but I was
wondering if there was an easier way.

Thanks!

Tj

--
TJ Luoma
TJ @ MacStories
Personal Website: luo.ma (aka RhymesWithDiploma.com)
Twitter: @tjluoma

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: is there a way to use *.{txt,zip,tbz,dmg} if one or more might be missing?
  2019-07-07 23:27 is there a way to use *.{txt,zip,tbz,dmg} if one or more might be missing? TJ Luoma
@ 2019-07-08  0:10 ` Bart Schaefer
  2019-07-08 10:44   ` Peter Stephenson
  0 siblings, 1 reply; 4+ messages in thread
From: Bart Schaefer @ 2019-07-08  0:10 UTC (permalink / raw)
  To: TJ Luoma; +Cc: Zsh Users

On Sun, Jul 7, 2019 at 4:28 PM TJ Luoma <luomat@gmail.com> wrote:
>
> Is there a way to do basically the same thing, but tell `mv` "if is at
> least one file with any of these extensions, then move to ~/dir/" ?

Use an alternation pattern instead of brace expansion:

    mv -vn *.(txt|zip|tbz|dmg) ~/dir/

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: is there a way to use *.{txt,zip,tbz,dmg} if one or more might be missing?
  2019-07-08  0:10 ` Bart Schaefer
@ 2019-07-08 10:44   ` Peter Stephenson
  2019-07-08 12:14     ` Mikael Magnusson
  0 siblings, 1 reply; 4+ messages in thread
From: Peter Stephenson @ 2019-07-08 10:44 UTC (permalink / raw)
  To: zsh-users

On Sun, 2019-07-07 at 17:10 -0700, Bart Schaefer wrote:
> On Sun, Jul 7, 2019 at 4:28 PM TJ Luoma <luomat@gmail.com> wrote:
> > 
> > 
> > Is there a way to do basically the same thing, but tell `mv` "if is at
> > least one file with any of these extensions, then move to ~/dir/" ?
> Use an alternation pattern instead of brace expansion:
> 
>     mv -vn *.(txt|zip|tbz|dmg) ~/dir/

I'm surprised to see I never added this to the FAQ.  It's getting
quite hard to search, though...

pws

diff --git a/Etc/FAQ.yo b/Etc/FAQ.yo
index c4f65e97a..a8d88ec7c 100644
--- a/Etc/FAQ.yo
+++ b/Etc/FAQ.yo
@@ -128,6 +128,7 @@ Chapter 3:  How to get various things to work
 3.27. What are these `^' and `~' pattern characters, anyway?
 3.28. How do I edit the input buffer in $EDITOR?
 3.29. Why does `which' output for missing commands go to stdout?
+3.30. Why doesn't the expansion mytt(foo.{tex,aux,pdf}) do what I expect?
 
 Chapter 4:  The mysteries of completion
 4.1. What is completion?
@@ -1995,6 +1996,44 @@ sect(Why does `which' output for missing commands go to stdout?)
   the exit status does reflect the fact the command can't be found.
 
 
+sect(Why doesn't the expansion mytt(*.{tex,aux,pdf}) do what I expect?)
+
+  Based on the behaviour of some other shells, you might guess that the
+  following expression:
+  verb(
+    echo *.{tex,aux,pdf}
+  )
+  would be the way to echo any files ending in mytt(.tex), mytt(.aux) or
+  mytt(.pdf) in the current directory.  Depending on your settings for
+  matching (see link(2.1)(21), in particular tt(NO_NOMATCH)), you may
+  see something else, in particular an error about (say) mytt(*.aux) if
+  there were no files ending mytt(.aux).
+
+  The reason for this is that the brace expansion isn't actually
+  a form of pattern matching.  Instead, the line above is equivalent to
+  verb(
+    echo *.tex *.aux *.pdf
+  )
+  giving you three separate patterns.  With the default mytt(NOMATCH)
+  behaviour in effect, any pattern that fails to match is an error.
+
+  However, there em(is) a way of doing exactly what you want, using
+  parentheses instead of braces:
+  verb(
+    echo *.(tex|aux|pdf)
+  )
+  This is now a pattern matching expression, so is considered as a
+  single pattern.  Now any file that exists will supress the
+  mytt(NOMATCH) behaviour, but you'll still get all the files that do
+  match.
+
+  This use of parentheses is special to zsh.  Modern Bourne-like shells
+  have a syntax like this, too, but with an mytt(@) in front of the
+  parentheses: again, see link(2.1)(21), and search for mytt(@+LPAR()).
+  This is harder for the user to remember but easier for the shell to
+  parse!
+
+
 chapter(The mysteries of completion)
 
 


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: is there a way to use *.{txt,zip,tbz,dmg} if one or more might be missing?
  2019-07-08 10:44   ` Peter Stephenson
@ 2019-07-08 12:14     ` Mikael Magnusson
  0 siblings, 0 replies; 4+ messages in thread
From: Mikael Magnusson @ 2019-07-08 12:14 UTC (permalink / raw)
  To: Peter Stephenson; +Cc: zsh-users

On 7/8/19, Peter Stephenson <p.stephenson@samsung.com> wrote:
> On Sun, 2019-07-07 at 17:10 -0700, Bart Schaefer wrote:
>> On Sun, Jul 7, 2019 at 4:28 PM TJ Luoma <luomat@gmail.com> wrote:
>> >
>> >
>> > Is there a way to do basically the same thing, but tell `mv` "if is at
>> > least one file with any of these extensions, then move to ~/dir/" ?
>> Use an alternation pattern instead of brace expansion:
>>
>>     mv -vn *.(txt|zip|tbz|dmg) ~/dir/
>
> I'm surprised to see I never added this to the FAQ.  It's getting
> quite hard to search, though...
>
> pws
>
> diff --git a/Etc/FAQ.yo b/Etc/FAQ.yo
> index c4f65e97a..a8d88ec7c 100644
> --- a/Etc/FAQ.yo
> +++ b/Etc/FAQ.yo
> @@ -128,6 +128,7 @@ Chapter 3:  How to get various things to work
>  3.27. What are these `^' and `~' pattern characters, anyway?
>  3.28. How do I edit the input buffer in $EDITOR?
>  3.29. Why does `which' output for missing commands go to stdout?
> +3.30. Why doesn't the expansion mytt(foo.{tex,aux,pdf}) do what I expect?

This part should probably say * too, not foo.

-- 
Mikael Magnusson

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, back to index

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-07-07 23:27 is there a way to use *.{txt,zip,tbz,dmg} if one or more might be missing? TJ Luoma
2019-07-08  0:10 ` Bart Schaefer
2019-07-08 10:44   ` Peter Stephenson
2019-07-08 12:14     ` Mikael Magnusson

zsh-users

Archives are clonable: git clone --mirror http://inbox.vuxu.org/zsh-users

Newsgroup available over NNTP:
	nntp://inbox.vuxu.org/vuxu.archive.zsh.users


AGPL code for this site: git clone https://public-inbox.org/ public-inbox