k[x_] := ( a=2x+1  ;  b=x^2  ;  c=3x ; a b c )
W = k[2];
{ a, b, c, W }

	{5, b, 3, 120}

small[x_] := If[ Abs[N[x]] < 1, True, False, dunno ]

Map[ small,      {0, 0.5, 1, 5, XXX, Pi/4}    ]

	{True, True, False, False, dunno, True}



small[x_] := If[ Abs[N[x]] < 1,
		Print[x, " is small."] ; a=0; True,
		Print[x, " isn't small."] ; a=99; False,
		Print[x, " is ???."] ; a=-17; dunno]

Map[ small,      {0, 0.5, 1, XXX, Pi-3}    ]


	0 is small.
	0.5 is small.
	1 isn't small.
	XXX is ???.
	-3 + Pi is small.

	{True, True, False, dunno, True}