REAL_INT_SUB_CONV : conv

SYNOPSIS
Conversion to perform subtraction on two integer literals of type :real.

DESCRIPTION
The call REAL_INT_SUB_CONV `c1 - c2` where c1 and c2 are integer literals of type :real, returns |- c1 - c2 = d where d is the canonical integer literal that is equal to c1 - c2. The literals c1 and c2 may be of the form &n or -- &n (with nonzero n in the latter case) and the result will be of the same form.

FAILURE CONDITIONS
Fails if applied to a term that is not the difference of two permitted integer literals of type :real.

EXAMPLE
  # REAL_INT_SUB_CONV `&33 - &77`;;
  val it : thm = |- &33 - &77 = -- &44

COMMENTS
The related function REAL_RAT_SUB_CONV subsumes this functionality, also applying to rational literals. Unless the restriction to integers is desired or a tiny efficiency difference matters, it should be used in preference.

SEE ALSO
INT_SUB_CONV, REAL_RAT_SUB_CONV, REAL_INT_REDUCE_CONV.