Hello, calculator!
(1+2) * (3^2) / 100 + 10000 - 99
expr=(1+2) * (3^2) / 100 + 10000 - 99
 calulcate result: 9901.27
(2^10)
expr=(2^10)
 calulcate result: 1024
(2^11)
expr=(2^11)
 calulcate result: 2048
2 * (3 / 999) + 8 ^ 2
expr=2 * (3 / 999) + 8 ^ 2
 calulcate result: 64.006006006006
(100 - 88) ^ (6+8)
expr=(100 - 88) ^ (6+8)
 calulcate result: 1283918464548864
((2+3)
calulcate error: InvalidExperssion, expr=((2+3)

(2)
expr=(2)
 calulcate result: 2
(999 + 1/ 2 * 5 * 7 +8)
expr=(999 + 1/ 2 * 5 * 7 +8)
 calulcate result: 999.0128205128206
(12.5 + 8)
expr=(12.5 + 8)
 calulcate result: 20.5
12.x + 6
TokenNotSupported("x is not supported")