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 return a % b; 79 } 80 81 default: 82 throw std::invalid_argument("Unrecognised operation"); 83 } 84 } 85 86 int evaluate(int substitute, std::vector<std::string>::iterator curr, 87 std::vector<std::string>::iterator& end) 88 { 89 bool isOperator = true; 90 std::optional<Operation> next = Operation::addition; 91 92 for (; curr != end; curr++) 93 { 94 if (isOperator) 95 { 96 next = expression::parseOperation(*curr); 97 if (!next) 98 { 99 break; 100 } 101 } 102 else 103 { 104 try 105 { 106 int constant = std::stoi(*curr); 107 substitute = evaluate(substitute, *next, constant); 108 } 109 catch (const std::invalid_argument&) 110 { 111 std::cerr << "Parameter not supported for templates " << *curr 112 << "\n"; 113 continue; 114 } 115 } 116 isOperator = !isOperator; 117 } 118 119 end = curr; 120 return substitute; 121 } 122 } // namespace expression 123