Warning: Method definition f(Any) overwritten

New to Julia
7

You want an anonymous function:

Simple solution:

function create_f(flag::Bool)
  if flag
    x -> x^2
  else
    x -> x^3
  end
end

The above solution is, however, not type stable:

julia> using Test

julia> @inferred create_f(true)
ERROR: return type var"#1#3" does not match inferred return type Union{var"#1#3", var"#2#4"}

A type stable solution:

function create_f(flag::Bool)
  m = flag ? 2 : 3
  let n = m
    x -> x^n
  end
end

Now the type is uniquely inferred:

julia> using Test

julia> @inferred create_f(true)
#1 (generic function with 1 method)
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