structurallyEquals
Checks whether another term is structurally equals to the current one or not. Structural equivalence is a looser type of equivalence (w.r.t. term equivalence) where:
numbers are compared by value, e.g.
1is structurally equal to1.0variables are always considered equal, e.g.
f(X)is structurally equal tof(_)
Return
true if the two terms are structurally equal, or false, otherwise