We describe comparison operations with null, but not with NaN, -INF and INF.

For NaN IEEE754, says that NaN is unordered and not equal to itself, meaning that NaN compared to anything, including NaN, is false except for != which is true.

This makes sense mathematically; however, this makes it very hard to find all resources with a property value of NaN (we would have to add a separate IsNaN() operator, and comparisons would have to account for this in their expressions). We could say that NaN==NaN, similar to how we say Null==Null to make it easier to search for Null values.

For INF, -INF, IEEE754 appears to define INF==INF and -INF==-INF, so we would have:
INF == INF: True
INF != INF: False
INF < INF: False
INF <= INF: True
INF > INF: False
INF >= INF: True
INF < <valid number>: False
INF <= <valid number>: False
INF > <valid number: True
INF >= <valid number>: True
INF > -INF: True
-INF == -INF: True
-INF != -INF: False
-INF < -INF: False
-INF <= -INF: True
-INF > -INF: False
-INF >= -INF: Tru
-INF < <valid number>: True
-INF <= <valid number>: True
-INF > <valid number>: False
-INF >= <valid number>: False
-INF > INF: False