// test: echo "cos (1, 2)" | calc.exe | grep -q 'error'
// test: echo "sqrt 2" | calc.exe | grep -q 'error'
// test: echo "pow (2)" | calc.exe | grep -q 'error'
-// test: echo "1.23456789" | calc.exe -p 3 | grep -q '1\.234'
+// test: echo "1.23456789" | calc.exe -p 4 | grep -q '=> 1\.235'
// test: echo . | calc.exe
// test: echo -e '1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1\n1 + 1' | calc.exe -n | grep -q 64
// test: echo -e '1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1 + 1\n1 + 1' | calc.exe -n | grep -q 2
// test: echo -e '1 }\n1 )\n1 , 2\n ' | calc.exe | grep -c error | xargs test 3 =
// test: echo -e 'print (1)\nquit' | calc.exe -v 3 | grep -q Print
// test: echo -e 'si\t\t (pi / 2)' | calc.exe | grep -q '=> 1'
+// test: echo -e '\t\t' | calc.exe | grep -q 'print'
// test: echo -e '1 + 1;\nans + 1' | calc.exe | grep -qv 2
// test: echo -e 'mem (3)\nsto (4, pi)' | calc.exe | grep -q "invalid index"
// test: echo -e 'sto (2, 3)\nmem (2)\ndisp' | calc.exe | grep -q 'storage: 0 3$'