For 1, use a heredoc to a noop. Sorry for the terse reply, on my phone. On 23 Mar 2013 05:07, "Richard Neill" <rn...@richardneill.org> wrote:
> Dear All, > > Might I suggest/request that "set +n" should undo the effect of > "set -n" ? > > For example: > > #!/bin/bash > echo one > set -n > echo two > set +n > echo three > > would print: > one > three > > > Here's why I think it would be useful: > > > 1. Bash doesn't have a block-comment mechanism, like /* ... */ > and this would provide one. > > 2. The documentation for "help set" says that flags can be undone with > "+", thus the inverse of -n is +n. > (though in contradiction , it also says that subsequent commands (which > would include the "set" are ignored) > > > 3. It would allow for a neat hack with polyglots. For example: > > #!/bin/bash -n > <?php /* > set +n > echo "Hello, from Bash" > exec /usr/bin/php -ddisplay_errors=E_ALL $0 $@ > */ > echo "Hello from PHP ".phpversion()."\n"; > //continue in PHP till the end of the file. > ?> > > > (there is actually a serious purpose to this, namely to create a php-cli > script that shows all errors, despite the settings in the system-wide > php-ini file) > > Example 3 works if you remove the "-n" and "set +n" parts, though it then > emits an annoying complaint about "?php: No such file or directory" > > > Thank you for your consideration, > > Best wishes, > > Richard > >
