There is a language out there (I want to say one of the
Algols, but it's
rather hard to search for this example) that allows you do
to:
if if == if then then = then else else = else
or how about:
if then = else then else = then else else = if
PL/I, maybe others. An attempt to keep your sanity is here:
http://pliedit.com/
This example should be enough to kill any proposal making keywords
"reusable".