// test: echo -e 'mem (3)\nclr\nquit' | calc.exe -v 3 | grep -q Clear
// test: echo -e 'prog (2, {arg (2) - arg (1)})\nprog (1, {cos (arg (1)^2)})\ncall (1, pi/6)\nprog (2, {arg (1) * 3})\ncall (2, 1, 2)\nls' | calc.exe | grep -q 'programs: 2 1'
// test: echo -e 'prog (1, {arg (2) - arg (1)})\ncall (1, 2, 3)\nls\nedit (1)\nprog (1, {arg (2) + arg (1)})\nedit (1)\ndel (1)\nquit' | calc.exe -v 3 | grep -q bye
// test: echo -e 'mem (3)\nclr\nquit' | calc.exe -v 3 | grep -q Clear
// test: echo -e 'prog (2, {arg (2) - arg (1)})\nprog (1, {cos (arg (1)^2)})\ncall (1, pi/6)\nprog (2, {arg (1) * 3})\ncall (2, 1, 2)\nls' | calc.exe | grep -q 'programs: 2 1'
// test: echo -e 'prog (1, {arg (2) - arg (1)})\ncall (1, 2, 3)\nls\nedit (1)\nprog (1, {arg (2) + arg (1)})\nedit (1)\ndel (1)\nquit' | calc.exe -v 3 | grep -q bye