IFS=:; ${-+:foo:var} skips the first empty element

[Stephane Chazelas]

With @(#)MIRBSD KSH R50 2014/06/29 on Debian:

$ IFS=:
$ set ${0+:foo:bar}
$ echo $#
2
$ echo "<$1>"
<foo>


Expected:

$ IFS=:
$ set ${0+:foo:bar}
$ echo $#
3
$ echo "<$1>"
<>

-- 
Stephane