eval, print, showstat

acer — Wed, 27 Feb 2013 15:08:46 Z

One can programmatically access the body of a procedure using the `eval` command. Eg. to subs into it, or get its inert form, or assign a copy of it to something else, etc.

By default one can also use just the `print` command to display the body of a procedure. This differs from `eval` in that it only prints. The return value from this operation is NULL, so it doesn't give programmatic access. (See also ?verboseproc)

To display line numbers, one can use the `showstat` command.

> restart:

> u:=x->x^2;
                      
                            2
                      x -> x 

> f:=eval(u);

                            2
                      x -> x 

> f(3);

                         9

> print(u);

                            2
                      x -> x

> showstat(u);

u := proc(x)
   1   x^2
end proc

Note that all of these will display without showing any comments present in the original source.

acer

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eval, print, showstat