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Comment: Add example for non-obvious backslashing behaviour
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| == Why is $(...) preferred over `` (backticks)? == | == Why is $(...) preferred over `...` (backticks)? == |
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| * Newbies who see {{{$()}}} don't normally press the wrong keys. On the other hand, newbie who see {{{`cmd`}}} often mangle it into {{{'cmd'}}} because they don't know what a backtick is. * Backslashes (\) inside backticks are handled in a non-obvious manner. ''(Example desired!)'' Inside {{{$()}}}, there are no such surprises. |
* Newbies who see {{{$()}}} don't normally press the wrong keys. On the other hand, newbies who see {{{`cmd`}}} often mangle it into {{{'cmd'}}} because they don't know what a backtick is. * Backslashes (\) inside backticks are handled in a non-obvious manner: {{{ echo "`echo \\a`" # prints a echo "`echo \\\a`" # prints \a echo "`echo \\\\a`" # prints \a}}} Inside {{{$()}}}, there are no such surprises. |
Why is $(...) preferred over `...` (backticks)?
For several reasons:
- It makes nesting command substitutions easier. Compare:
x=$(grep $(dirname "$path") file) x=`grep \`dirname "$path"\` file`
- It's easier to read.
Newbies who see $() don't normally press the wrong keys. On the other hand, newbies who see `cmd` often mangle it into 'cmd' because they don't know what a backtick is.
- Backslashes (\) inside backticks are handled in a non-obvious manner:
echo "`echo \\a`" # prints a echo "`echo \\\a`" # prints \a echo "`echo \\\\a`" # prints \a
Inside $(), there are no such surprises.
The only time backticks are preferred is when writing code for the oldest Bourne shells, which do not know about $().