test_scan = ->
  if DEBUG then console.log "test_scan ----------------------------"

  run_test [

    "a^^b",
    "a^^ ? b\nStop: syntax error",

    "(a+b",
    "(a+b ? \nStop: ) expected",

    "quote(1/(x*log(a*x)))",  # test case A
    "1/(x*log(a*x))",

    "\"hello",
    "\"hello ? \nStop: runaway string",

    # make sure question mark can appear after newlines

    "a+\nb+\nc+",
    "a+\nb+\nc+ ? \nStop: syntax error",

    # this bug fixed in version 30 (used to give one result, 14)

    "(1+1)",
    "2",

    "2+2\n(3+3)",
    "4\n6",

    # plus and minus cannot cross newline

    "1\n-1",
    "1\n-1",

    "1\n+1",
    "1\n1",

    # implicit multiplication is parsed fine in
    # in the obvious cases where the first factor
    # is a "naked" number. Note that
    # (2)(a) doesn't work (yet) instead.
    # In many other cases such as a(b) it's in
    # principle impossible at parse time to turn that
    # into a multiplication because the first factor
    # could be a function, so that'd be a function
    # call.

    "2(a) * 2a",
    "4*a^2",

    "2a3b",
    "2*a3b",

    "2a 3b",
    "6*a*b",

    "2 a 3b",
    "6*a*b",

    "2 a 3 b",
    "6*a*b",

    "2(a)3(b)",
    "6*a*b",

    "2(a)b*3",
    "6*a*b",

    "(a)2 * 2a",
    "4*a^2",

    "3 (2 x^3 + x^2 - 23 x + 20)",
    "6*x^3+3*x^2-69*x+60",

  ]