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null word list in for loops in bash-2.05.8 not allowed


From: cpg
Subject: null word list in for loops in bash-2.05.8 not allowed
Date: Sun, 18 Nov 2001 00:38:37 -0600

Configuration Information [Automatically generated, do not change]:
Machine: i386
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='i386' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i386-redhat-linux-gnu' 
-DCONF_VENDOR='redhat' -DSHELL -DHAVE_CONFIG_H  -D_GNU_SOURCE 
-D_FILE_OFFSET_BITS=64  -I.  -I. -I./include -I./lib -I/usr/include -O2 
-march=i386 -mcpu=i686
uname output: Linux caesar 2.4.7-10smp #1 SMP Thu Sep 6 17:09:31 EDT 2001 i686 
unknown
Machine Type: i386-redhat-linux-gnu

Bash Version: 2.05
Patch Level: 8
Release Status: release

Description:

        it is not clear if this is a bug:

                bash$ for i in ; do echo hi; done
                bash: syntax error near unexpected token `;'
                bash$

        the manual says the following:

        "If the expansion of the items following in results in an
        empty list, no commands are executed, and the return status is
        0."

        what makes me doubt is this:

                bash$ for i in $NOTHING ; do echo hi; done
                bash$

        with NOTHING not being defined. the problem is that a makefile
        we have issues this loop:

                for i in $(SOMETHING); do \
                        install $$i ..... ; \
                done

        but some times, $(SOMETHING) expands to nothing at all in the
        makefile and fails the compilation process with the syntax
        error mentioned above. i think what is going on is that it is
        passed down on the shell in the form with nothing in between
        the 'in' and the ';' and therefore we get the failure.

        is there any harm to doing no iterations when nothing is suppied.
        seems clean and elegant enough. is this a matter of standards, or is
        it a bug?

        if it is expected behavior, do you have a proposal of a clean
        solution in the makefile?

        this is the bash that comes in redhat 7.2, btw.

Repeat-By:

        for i in ; do echo hi; done

Fix:



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