Testing parametric code with print statements

[Brandon Barker]

Say you want to inspect the implementation of some parametric code dynamically by printing data on test cases. print() does not work for any t@ype, so it would be nice to assert:

a is printable

a = a specific type .

So as to not "dumb down" the implementation by removing the parameterization.

I tried to do this with a praxi but failed.

Or, is there some other alternative?

[gmhwxi]

You can use 'print_val<a> (...)' or fprint_val<a> (...)'.

[Brandon Barker]

Great, I implemented it in ATS1 like this, and show how to use it to print a list_vt:

extern

fun{a:t0p} print_val(x: a): void

implement

print_val<int> (x) = print(x)

fun{a:t0p} print_lvt(xsl: !List_vt (a)): void =

begin (

list_vt_foreach_fun<a> (xsl, lam x =<1> (print_val<a> (x); print ' '));

print_newline();

) end

In ATS2, this relies on the function 'tostrptr_val'. Perhaps I am just failing with my greps, but would it be useful if I implemented this for some of the common types (int, double, char, strings, etc)?

[gmhwxi]

These have already been implemented:

val () = print_val<int> (0)
val () = print_val<string> ("0")
val () = print_val<double> (0.0)

To print out a list, you can use fprint_list or fprint_list_sep.

On Tuesday, January 14, 2014 3:39:01 PM UTC-5, Brandon Barker wrote: