bug#20764: 25.0.50; Minor improvements for calculator.el

[nljlistbox2@gmail.com (N. Jackson)]

At 15:39 -0300 on Sunday 2015-06-07, Chris Zheng wrote:

> Hello, Emacs.
>
> I find the calculator.el in Emacs is handy.  However, there are two
> things I'd like to see changed.
>
> 1. Press F1 results in `??bad key?? (f1)'.
> 2. Can't enter exponent by `E'.
>
> Both of them can be reproduced by: (1) emacs -Q; (2) M-x calculator; (3)
> Press `F1' or `E'.  I have the following patch trying to fix the above
> two things.  Please let me know if I'm doing things wrong.
>
> * calculator.el (calculator-mode-map): Bind `E' for `calculator-exp'.
> (calculator-last-input): Fix a bug that press F1 results in
> `??bad key?? (f1)'.
> ---
>  lisp/calculator.el | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/lisp/calculator.el b/lisp/calculator.el
> index 4027887..d20faa3 100644
> --- a/lisp/calculator.el
> +++ b/lisp/calculator.el
> @@ -394,7 +394,7 @@ Used for repeating operations in calculator-repR/L.")
>                                       [kp-5] [kp-6] [kp-7] [kp-8] [kp-9])
>               (calculator-op          [kp-divide] [kp-multiply])
>               (calculator-decimal     "." [kp-decimal])
> -             (calculator-exp         "e")
> +             (calculator-exp         "e" "E")
>               (calculator-dec/deg-mode "D")
>               (calculator-set-register "s")
>               (calculator-get-register "g")
> @@ -1219,7 +1219,7 @@ arguments."
>    "Last char (or event or event sequence) that was read.
>  Use KEYS if given, otherwise use `this-command-keys'."
>    (let ((inp (or keys (this-command-keys))))
> -    (if (or (stringp inp) (not (arrayp inp)))
> +    (if (or (stringp inp) (not (arrayp inp)) (member inp '([f1] [help])))
>        inp
>        ;; Translates kp-x to x and [tries to] create a string to lookup
>        ;; operators; assume all symbols are translatable via

Two cents from another calc user:

`E' is already bound. It is bound to calc-exp, the exponential function
e^x. For example (where "Calc: " is the calculator prompt and the stack
is shown above it):

    --- Emacs Calculator Mode ---
        .

Calc: 1 <RET>

    --- Emacs Calculator Mode ---
    1:  1
        .

Calc: E

    --- Emacs Calculator Mode ---
    1:  2.71828182846
        .

This is not to be confused with `e' which introduces the exponent
when entering a number in scientific notation:

    --- Emacs Calculator Mode ---
        .

Calc: 1e3

    --- Emacs Calculator Mode ---
    1:  1000
        .

It would be a disaster if the exponential function were no longer
available!

As far as F1 for help goes, it is incongruent with the calculator
interface. For different types of help, `?', `h i', `C-h m' etc. are
available.

However, F1 is familiar for users from other platforms, so I think it
might be a good addition for the benefit of new or infrequent users.