Re: [SPOILER] Re: Perl Quiz of the Week #25 (RPN calculator)

Mark Jason Dominus <[email protected]> writes:

> In PostScript you define a procedure by doing something like:
>
> 	{ 2 mul } /double def
>
> After processing the '}' operator, the stack contains an anonymous
> function.  '/double' pushes the "name object" representing the name
> "double", and then "def" is a binary operator which expects a name and
> a value and associates the two in the current dictionary.

I extended my calculator with this type of function definition and it
is now possible to define 'tan' using only the operators specified in
the original quiz.  There are a number of other functions that are
interesting to define if you remember (or look up ;-) the
trigonometric identities.

Jon