How to implement non-associative operators?

[teiesti]

I am trying to use pest to implement a language featuring operators that are left-associative (like +) and non-associative (like <). With other words, a + b + c should translate to (a + b) + c while a < b < c is a syntax error.

I learnt that I can use the PrattParser for precedence parsing. However, when defining operators I merely have the option to make them left or right associative. Is there a preferred way to define non-associative operators?

See also