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Re: No tilde expansion right after a quotation
From: |
Angel Tsankov |
Subject: |
Re: No tilde expansion right after a quotation |
Date: |
Mon, 16 Feb 2009 02:46:13 +0200 |
Jon Seymour wrote:
> On Mon, Feb 16, 2009 at 10:22 AM, Paul Jarc <prj@po.cwru.edu> wrote:
>> Jon Seymour <jon.seymour@gmail.com> wrote:
>>> If the builtin echo fails it will be because the bash interpreter
>>> has suffered a catastrophic failure of some kind [ e.g. run out of
>>> memory ]. Once that has happened, all bets are off anyway.
>>
>> Probably true, but command substitution forks a separate process, so
>> that can fail for reasons external to the bash process.
>>
>> Here's another possibility:
>> CPATH=${CPATH:+$CPATH:}${#+~usr1/blah/blah}
>>
>
> Paul,
>
> Out of interest, how does one derive that outcome from the documented
> behaviour of bash? That is, which expansion rules are being invoked?
${#+~usr1/blah/blah} probably refers to $#. Strangely, this variable seems
to be defined even when not executing any function. However, in this case
"echo $#" prints "$#"! The expansion rules are exactly two:
${parameter:+word}
(http://www.gnu.org/software/bash/manual/bashref.html#Shell-Parameters,
3.5.3 Shell Parameter Expansion) and ${parameter} (3.5.3 Shell Parameter
Expansion)
-Angel
- Re: No tilde expansion right after a quotation, (continued)
- Re: No tilde expansion right after a quotation, Paul Jarc, 2009/02/15
- Re: No tilde expansion right after a quotation, Angel Tsankov, 2009/02/15
- Re: No tilde expansion right after a quotation, Jon Seymour, 2009/02/15
- Re: No tilde expansion right after a quotation, Paul Jarc, 2009/02/15
- Re: No tilde expansion right after a quotation, Angel Tsankov, 2009/02/15
- Re: No tilde expansion right after a quotation, Jon Seymour, 2009/02/15
- Re: No tilde expansion right after a quotation, Paul Jarc, 2009/02/15
- Re: No tilde expansion right after a quotation, Jon Seymour, 2009/02/15
- Re: No tilde expansion right after a quotation, Paul Jarc, 2009/02/15
- Re: No tilde expansion right after a quotation, Jon Seymour, 2009/02/15
- Re: No tilde expansion right after a quotation,
Angel Tsankov <=
- Re: No tilde expansion right after a quotation, Eric Blake, 2009/02/15
- Re: No tilde expansion right after a quotation, Angel Tsankov, 2009/02/16
- Re: No tilde expansion right after a quotation, Dave B, 2009/02/16
- Re: No tilde expansion right after a quotation, Angel Tsankov, 2009/02/16
- Re: No tilde expansion right after a quotation, Eric Blake, 2009/02/16
- Re: No tilde expansion right after a quotation, Chet Ramey, 2009/02/16