unused-binding

Flag a local variable that is assigned but never read in the same scope. Parameters, loop and catch variables, struct fields, type parameters, and top-level definitions are exempt, since those are meaningful even when unread. Names beginning with _ are skipped, following Julia’s throwaway convention.

tmp is assigned inside f but never used:

function f(x)
    tmp = x + 1
    return x
end

example.jl:2:5: warning[unused-binding] local variable `tmp` is assigned but never used