Remove redundant listZ function & use listZZ instead

Also stop calling it from Matrix_List & Matrix^List; it's called later
down the line by submatrixFree.

Author: d-torrance

M2/Macaulay2/m2/engine.m2

@@ -53,7 +53,7 @@ isSmall := i -> class i === ZZ and i < 2^15 and i > -2^15
 isCount := i -> class i === ZZ and i >= 0 and i < 2^15
 isListOfIntegers = x -> instance(x, List) and all(x,i -> class i === ZZ)
 isListOfListsOfIntegers = x -> instance(x, List) and all(x,isListOfIntegers)
-listZ = listZZ = v -> if isListOfIntegers(v = toList splice v) then v else error "expected a list of integers"
+listZZ = v -> if isListOfIntegers(v = toList splice v) then v else error "expected a list of integers"
 checkCount := i -> if not isCount i then error "expected a small positive integer"
 
 fixup1 := method(Dispatch => Thing)			    -- stage 1, everything except Tiny and Small

M2/Macaulay2/m2/matrix.m2

@@ -431,8 +431,8 @@ Matrix || Number := (f,g) -> concatRows(f,g*id_(source f))
 -----------------------------------------------------------------------------
 -- submatrix, submatrixByDegrees
 -----------------------------------------------------------------------------
-Matrix _ List := Matrix => (f,v) -> submatrix(f,listZ splice v)	-- get some columns
-Matrix ^ List := Matrix => (f,v) -> submatrix(f,listZ splice v,) -- get some rows
+Matrix _ List := Matrix => (f,v) -> submatrix(f, v)  -- get some columns
+Matrix ^ List := Matrix => (f,v) -> submatrix(f, v,) -- get some rows
 
 Matrix _ ZZ := Vector => (m,i) -> (
      R := ring m;

M2/Macaulay2/m2/matrix2.m2

@@ -525,13 +525,9 @@ support Ideal       := I -> support generators I
 --------------------
 homogenize = method()
 
-listZ := v -> (
-     if not all(v,i -> class i === ZZ) then error "expected list of integers";
-     )
-
 homogCheck := (R, f, v, wts) -> (
      if R =!= ring v then error "homogenization requires variable in the same ring";
-     listZ wts;
+     wts = listZZ wts;
      if degreeLength R =!= 1 then error "homogenization requires degrees of length 1";
      -- if # wts != numgens ring f then error "homogenization weight vector has incorrect length";
      i := index v;