1 /* 2 // Copyright (c) 2017 Intel Corporation 3 // Copyright (c) 2022 IBM Corp. 4 // 5 // Licensed under the Apache License, Version 2.0 (the "License"); 6 // you may not use this file except in compliance with the License. 7 // You may obtain a copy of the License at 8 // 9 // http://www.apache.org/licenses/LICENSE-2.0 10 // 11 // Unless required by applicable law or agreed to in writing, software 12 // distributed under the License is distributed on an "AS IS" BASIS, 13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 // See the License for the specific language governing permissions and 15 // limitations under the License. 16 */ 17 18 #include "expression.hpp" 19 20 #include <iostream> 21 #include <stdexcept> 22 23 namespace expression 24 { 25 std::optional<Operation> parseOperation(std::string& op) 26 { 27 if (op == "+") 28 { 29 return Operation::addition; 30 } 31 if (op == "-") 32 { 33 return Operation::subtraction; 34 } 35 if (op == "*") 36 { 37 return Operation::multiplication; 38 } 39 if (op == R"(%)") 40 { 41 return Operation::modulo; 42 } 43 if (op == R"(/)") 44 { 45 return Operation::division; 46 } 47 48 return std::nullopt; 49 } 50 51 int evaluate(int a, Operation op, int b) 52 { 53 switch (op) 54 { 55 case Operation::addition: 56 { 57 return a + b; 58 } 59 case Operation::subtraction: 60 { 61 return a - b; 62 } 63 case Operation::multiplication: 64 { 65 return a * b; 66 } 67 case Operation::division: 68 { 69 if (b == 0) 70 { 71 throw std::runtime_error( 72 "Math error: Attempted to divide by Zero\n"); 73 } 74 return a / b; 75 } 76 case Operation::modulo: 77 { 78 if (b == 0) 79 { 80 throw std::runtime_error( 81 "Math error: Attempted to divide by Zero\n"); 82 } 83 return a % b; 84 } 85 86 default: 87 throw std::invalid_argument("Unrecognised operation"); 88 } 89 } 90 91 int evaluate(int substitute, std::vector<std::string>::iterator curr, 92 std::vector<std::string>::iterator& end) 93 { 94 bool isOperator = true; 95 std::optional<Operation> next = Operation::addition; 96 97 for (; curr != end; curr++) 98 { 99 if (isOperator) 100 { 101 next = expression::parseOperation(*curr); 102 if (!next) 103 { 104 break; 105 } 106 } 107 else 108 { 109 try 110 { 111 int constant = std::stoi(*curr); 112 substitute = evaluate(substitute, *next, constant); 113 } 114 catch (const std::invalid_argument&) 115 { 116 std::cerr << "Parameter not supported for templates " << *curr 117 << "\n"; 118 continue; 119 } 120 } 121 isOperator = !isOperator; 122 } 123 124 end = curr; 125 return substitute; 126 } 127 } // namespace expression 128