[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Behavior of ${var/*/text} has changed
From: |
Eric Pruitt |
Subject: |
Behavior of ${var/*/text} has changed |
Date: |
Fri, 16 Sep 2016 12:06:53 -0700 |
User-agent: |
Mutt/1.5.23 (2014-03-12) |
Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64'
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='x86_64-unknown-linux-gnu'
-DCONF_VENDOR='unknown' -DLOCALEDIR='/usr/local/share/locale' -DPACKAGE='bash'
-DSHELL -DHAVE_CONFIG_H -I. -I. -I./include -I./lib -g -O2
-Wno-parentheses -Wno-format-security
uname output: Linux sinister 3.16.0-4-amd64 #1 SMP Debian 3.16.36-1+deb8u1
(2016-09-03) x86_64 GNU/Linux
Machine Type: x86_64-unknown-linux-gnu
Bash Version: 4.4
Patch Level: 0
Release Status: release
Description:
In Bash 4.3, "${var/*/text}" would generate "" if var was a zero-length
string and "text" if it contained at least one character. In Bash 4.4,
this
is no longer the case. I'm not sure if this is necessarily a bug, but I
was
unable to find this change in behavior in the change log or man page.
Repeat-By:
Bash 4.3:
ericpruitt@sinister:~$ echo ${VAR/*/VAR was not empty}
VAR was not empty
ericpruitt@sinister:~$ VAR=
ericpruitt@sinister:~$ echo ${VAR/*/VAR was not empty}
ericpruitt@sinister:~$
Bash 4.4:
ericpruitt@sinister:~$ VAR=NotEmpty
ericpruitt@sinister:~$ echo ${VAR/*/VAR was not empty}
VAR was not empty
ericpruitt@sinister:~$ VAR=
ericpruitt@sinister:~$ echo ${VAR/*/VAR was not empty}
VAR was not empty
ericpruitt@sinister:~$
Fix:
As a work-around, I have changed the expressions I'm using from
${VAR/*/...} to ${VAR/?*/...}. Since it is not clear to me if this is
actually a bug, I'm not sure what that fix should be. Maybe there
should be a new "compat..." option.
- Behavior of ${var/*/text} has changed,
Eric Pruitt <=
Re: Behavior of ${var/*/text} has changed, Chet Ramey, 2016/09/17