In sh, is '[' a portable synonym for 'test'?

[Guy Harris]

> 	if test -f "$1"	<= 15 keystrokes + <CR>
> vs.
> 	if [ -f "$1" ]	<= 14 keystrokes + <CR>
> 
> Which is more readable?

The latter, obviously; it reads more like a conditional statement rather
than a command.  It may be *implemented* as a command (which, if the command
isn't builtin, slows it down - somebody who complained that "test" shouldn't
be built in was later seen using a "case" statement instead of an "if" and a
"test" in order to make it run faster), but that fact isn't relevant to
understanding what it *does*.

Good grief, do you think that people use the square bracket to save one
measly keystroke?  That's not why it's there - it's there to improve the
readability of the statement.

	Guy Harris