"loop"? In particular, a RULE is like an equation for 'f' that
is *always* inlined if it is applicable. We do *not* disable
rules for loop-breakers. It's up to whoever makes the rules to
- make sure that the rules themselves alwasys terminate. See Note
+ make sure that the rules themselves always terminate. See Note
[Rules for recursive functions] in Simplify.lhs
Hence, if