test_sum = ->
  run_test [

    # no evaluation in case there are
    # symbolic variables
    "sum(body + k,k,b,c)",
    "sum(body+k,k,b,c)",

    "f=sum(a^k,k,0,9)",
    "",

    "eval(f,a,-1/2)",
    "341/512",

    # Leibniz formula for π as a series
    "sum(float((-1)^k * (1/(2*k + 1))),k,0,100)*4",
    "3.151493...",

    # -------------------

    "f(a,b)=sum(k,k,a,b)",
    "",

    "f(0,1)",
    "1",

    # --- cleanup

    "f = quote(f)",
    "",

  ]