sml - Output is truncated with #-signs in the REPL -

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i wrote function works expected don't understand why output that.

function:

datatype prop = atom of string | not of prop | , of prop*prop | or of prop*prop;   (* xor = (a , not b) or (not or b) *)  local  fun do_xor (alpha,beta) = or( and( alpha, not(beta) ), or(not(alpha), beta))  in fun xor (alpha,beta) = do_xor(alpha,beta); end;

test:

val result = xor(atom "a",atom "b");

output:

val result = or (and (atom #,not #),or (not #,atom #)) : prop

this output restriction (yes, it's confusing) - default depth of value printouts in top-level (interactive shell) limited small number (i.e. 5). skipped parts printed #.

you can override depth - @ least, in sml-nj - printdepth variable:

control.print.printdepth := 1024;

p.s. way, don't need separate do_xor , local function here - just

fun xor(alpha, beta) = or(...);

will do.


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