1 | namespace HeuristicLab.Problems.ProgramSynthesis.Push.Expressions {
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2 | using System;
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3 | using System.Linq;
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4 |
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5 | using Attributes;
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6 | using Interpreter;
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7 | using Stack;
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8 |
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9 | [PushExpression(StackTypes.String, "STRING.FROMINTEGER", StackTypes.Integer)]
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10 | public class StringFromIntegerExpression : StatelessExpression {
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11 | public override bool Eval(IInternalPushInterpreter interpreter) {
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12 | if (interpreter.IntegerStack.IsEmpty)
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13 | return false;
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14 |
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15 | var value = interpreter.IntegerStack.Pop();
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16 | interpreter.StringStack.Push(value.ToString());
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17 | return true;
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18 | }
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19 | }
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20 |
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21 | [PushExpression(StackTypes.String, "STRING.FROMFLOAT", StackTypes.Float)]
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22 | public class StringFromFloatExpression : StatelessExpression {
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23 | public override bool Eval(IInternalPushInterpreter interpreter) {
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24 | if (interpreter.FloatStack.IsEmpty)
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25 | return false;
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26 |
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27 | var value = interpreter.FloatStack.Pop();
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28 | interpreter.StringStack.Push(value.ToString());
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29 | return true;
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30 | }
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31 | }
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32 |
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33 | [PushExpression(StackTypes.String, "STRING.FROMBOOLEAN", StackTypes.Boolean)]
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34 | public class StringFromBooleanExpression : StatelessExpression {
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35 | public override bool Eval(IInternalPushInterpreter interpreter) {
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36 | if (interpreter.BooleanStack.IsEmpty)
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37 | return false;
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38 |
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39 | var value = interpreter.BooleanStack.Pop();
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40 | interpreter.StringStack.Push(value.ToString());
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41 | return true;
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42 | }
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43 | }
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44 |
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45 | [PushExpression(StackTypes.String, "STRING.FROMCHAR", StackTypes.Char)]
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46 | public class StringFromCharExpression : StatelessExpression {
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47 | public override bool Eval(IInternalPushInterpreter interpreter) {
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48 | if (interpreter.CharStack.IsEmpty)
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49 | return false;
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50 |
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51 | var value = interpreter.CharStack.Pop();
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52 | interpreter.StringStack.Push(value.ToString());
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53 | return true;
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54 | }
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55 | }
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56 |
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57 | [PushExpression(StackTypes.String, "STRING.CONCAT")]
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58 | public class StringConcatExpression : StatelessExpression {
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59 | public override bool Eval(IInternalPushInterpreter interpreter) {
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60 | if (interpreter.StringStack.Count < 2 ||
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61 | interpreter.StringStack.Top.Length + interpreter.StringStack[1].Length >= interpreter.Configuration.MaxStringLength)
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62 | return false;
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63 |
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64 | var str = interpreter.StringStack.Pop();
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65 | interpreter.StringStack.SetTop(str + interpreter.StringStack.Top);
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66 | return true;
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67 | }
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68 | }
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69 |
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70 | /// <summary>
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71 | /// Conj char onto string
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72 | /// </summary>
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73 | [PushExpression(StackTypes.String, "STRING.CONJCHAR", StackTypes.Char)]
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74 | public class StringConjCharExpression : StatelessExpression {
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75 | public override bool Eval(IInternalPushInterpreter interpreter) {
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76 | if (interpreter.StringStack.IsEmpty ||
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77 | interpreter.CharStack.IsEmpty ||
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78 | interpreter.StringStack.Top.Length + 1 >= interpreter.Configuration.MaxStringLength)
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79 | return false;
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80 |
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81 | var c = interpreter.CharStack.Pop();
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82 | interpreter.StringStack.SetTop(interpreter.StringStack.Top + c);
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83 | return true;
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84 | }
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85 | }
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86 |
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87 | [PushExpression(StackTypes.String, "STRING.TAKE", StackTypes.Integer)]
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88 | public class StringTakeExpression : StatelessExpression {
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89 | public override bool Eval(IInternalPushInterpreter interpreter) {
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90 | if (interpreter.StringStack.IsEmpty ||
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91 | interpreter.IntegerStack.IsEmpty)
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92 | return false;
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93 |
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94 | var value = interpreter.IntegerStack.Pop();
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95 |
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96 | if (value < 0) {
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97 | return true;
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98 | }
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99 |
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100 | var str = interpreter.StringStack.Top;
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101 |
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102 | if (str.Length > 0) {
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103 | value = Math.Min(str.Length - 1, value);
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104 | interpreter.StringStack.SetTop(str.Substring(0, (int)value));
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105 | }
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106 |
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107 | return true;
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108 | }
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109 | }
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110 |
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111 | [PushExpression(StackTypes.String, "STRING.SUBSTRING", StackTypes.Integer)]
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112 | public class StringSubstringExpression : StatelessExpression {
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113 | public override bool Eval(IInternalPushInterpreter interpreter) {
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114 | if (interpreter.StringStack.IsEmpty ||
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115 | interpreter.IntegerStack.Count < 2)
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116 | return false;
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117 |
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118 | var str = interpreter.StringStack.Top;
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119 | var firstValue = interpreter.IntegerStack[1];
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120 | var secondValue = interpreter.IntegerStack.Top;
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121 | interpreter.IntegerStack.Remove(2);
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122 |
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123 | var first = Math.Min(str.Length - 1, Math.Max(firstValue, 0));
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124 | var second = Math.Min(str.Length - 1, Math.Max(secondValue, first));
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125 | var length = second - first;
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126 |
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127 | if (length > 0)
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128 | interpreter.StringStack.SetTop(str.Substring((int)first, (int)length));
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129 |
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130 | return true;
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131 | }
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132 | }
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133 |
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134 | [PushExpression(StackTypes.String, "STRING.FIRST")]
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135 | public class StringFirstExpression : StatelessExpression {
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136 | public override bool Eval(IInternalPushInterpreter interpreter) {
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137 | if (interpreter.StringStack.IsEmpty ||
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138 | interpreter.StringStack.Top.Length == 0)
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139 | return false;
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140 |
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141 | interpreter.StringStack.SetTop(interpreter.StringStack.Top[0].ToString());
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142 | return true;
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143 | }
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144 | }
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145 |
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146 |
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147 | [PushExpression(StackTypes.String, "STRING.LAST")]
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148 | public class StringLastExpression : StatelessExpression {
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149 | public override bool Eval(IInternalPushInterpreter interpreter) {
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150 | if (interpreter.StringStack.IsEmpty ||
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151 | interpreter.StringStack.Top.Length == 0)
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152 | return false;
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153 |
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154 | var str = interpreter.StringStack.Top;
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155 | var c = str[str.Length - 1].ToString();
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156 | interpreter.StringStack.SetTop(c);
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157 | return true;
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158 | }
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159 | }
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160 |
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161 | [PushExpression(StackTypes.String, "STRING.NTH", StackTypes.Integer)]
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162 | public class StringNthExpression : StatelessExpression {
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163 | public override bool Eval(IInternalPushInterpreter interpreter) {
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164 | if (interpreter.StringStack.IsEmpty ||
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165 | interpreter.IntegerStack.IsEmpty ||
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166 | interpreter.StringStack.Top.Length == 0)
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167 | return false;
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168 |
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169 | var str = interpreter.StringStack.Top;
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170 | var index = str.Length == 1 ? 0 : (int)Math.Abs(interpreter.IntegerStack.Pop() % (str.Length - 1));
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171 | var c = str[index].ToString();
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172 | interpreter.StringStack.SetTop(c);
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173 | return true;
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174 | }
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175 | }
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176 |
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177 | [PushExpression(StackTypes.String, "STRING.REST")]
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178 | public class StringRestExpression : StatelessExpression {
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179 | public override bool Eval(IInternalPushInterpreter interpreter) {
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180 | if (interpreter.StringStack.IsEmpty ||
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181 | interpreter.StringStack.Top.Length == 0)
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182 | return false;
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183 |
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184 | var str = interpreter.StringStack.Top;
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185 | interpreter.StringStack.SetTop(str.Length == 1 ? string.Empty : str.Substring(1, str.Length - 1));
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186 | return true;
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187 | }
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188 | }
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189 |
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190 | [PushExpression(StackTypes.String, "STRING.BUTLAST")]
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191 | public class StringButLastExpression : StatelessExpression {
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192 | public override bool Eval(IInternalPushInterpreter interpreter) {
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193 | if (interpreter.StringStack.IsEmpty ||
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194 | interpreter.StringStack.Top.Length == 0)
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195 | return false;
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196 |
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197 | var str = interpreter.StringStack.Top;
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198 | interpreter.StringStack.SetTop(str.Length == 1 ? string.Empty : str.Substring(0, str.Length - 1));
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199 | return true;
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200 | }
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201 | }
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202 |
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203 | [PushExpression(StackTypes.String, "STRING.LENGTH", StackTypes.Integer)]
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204 | public class StringLengthExpression : StatelessExpression {
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205 | public override bool Eval(IInternalPushInterpreter interpreter) {
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206 | if (interpreter.StringStack.IsEmpty)
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207 | return false;
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208 |
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209 | var str = interpreter.StringStack.Pop();
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210 | interpreter.IntegerStack.Push(str.Length);
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211 | return true;
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212 | }
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213 | }
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214 |
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215 | [PushExpression(StackTypes.String, "STRING.REVERSE")]
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216 | public class StringReverseExpression : StatelessExpression {
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217 | public override bool Eval(IInternalPushInterpreter interpreter) {
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218 | if (interpreter.StringStack.IsEmpty)
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219 | return false;
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220 |
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221 | interpreter.StringStack.SetTop(interpreter.StringStack.Top.Reverse().ToString());
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222 | return true;
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223 | }
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224 | }
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225 |
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226 | [PushExpression(StackTypes.String, "STRING.PARSETOCHARS")]
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227 | public class StringParseToCharsExpression : StatelessExpression {
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228 | public override bool Eval(IInternalPushInterpreter interpreter) {
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229 | if (interpreter.StringStack.IsEmpty)
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230 | return false;
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231 |
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232 | if (interpreter.StringStack.Top.Length == 0) {
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233 | interpreter.StringStack.Pop();
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234 | return true;
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235 | }
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236 |
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237 | var str = interpreter.StringStack.Top;
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238 | interpreter.StringStack.SetTop(str[0].ToString());
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239 |
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240 | if (str.Length > 1) {
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241 | var chars = new string[str.Length - 1];
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242 | for (var i = 0; i < str.Length - 1; i++) {
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243 | chars[i] = str[i + 1].ToString();
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244 | }
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245 |
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246 | interpreter.StringStack.Push(chars);
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247 | }
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248 |
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249 | return true;
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250 | }
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251 | }
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252 |
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253 | [PushExpression(StackTypes.String, "STRING.SPLIT")]
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254 | public class StringSplitExpression : StatelessExpression {
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255 | public override bool Eval(IInternalPushInterpreter interpreter) {
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256 | if (interpreter.StringStack.IsEmpty)
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257 | return false;
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258 |
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259 | var words = interpreter.StringStack.Top.Trim().Split();
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260 |
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261 | if (words.Length == 0)
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262 | return false;
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263 |
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264 | interpreter.StringStack.SetTop(words[0]);
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265 |
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266 | if (words.Length > 1)
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267 | interpreter.StringStack.Push(words, 1);
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268 |
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269 | return true;
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270 | }
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271 | }
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272 |
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273 | /// <summary>
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274 | /// True if top string is empty
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275 | /// </summary>
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276 |
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277 | [PushExpression(StackTypes.String, "STRING.EMPTYSTRING", StackTypes.Boolean)]
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278 | public class StringEmptyStringExpression : StatelessExpression {
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279 | public override bool Eval(IInternalPushInterpreter interpreter) {
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280 | if (interpreter.StringStack.IsEmpty)
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281 | return false;
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282 |
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283 | var str = interpreter.StringStack.Pop();
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284 | interpreter.BooleanStack.Push(str.Length == 0);
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285 | return true;
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286 | }
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287 | }
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288 |
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289 | /// <summary>
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290 | /// True if top string is a substring of second string; false otherwise
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291 | /// </summary>
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292 | [PushExpression(StackTypes.String, "STRING.CONTAINS", StackTypes.Boolean)]
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293 | public class StringContainsExpression : StatelessExpression {
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294 | public override bool Eval(IInternalPushInterpreter interpreter) {
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295 | if (interpreter.StringStack.Count < 2)
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296 | return false;
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297 |
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298 | var first = interpreter.StringStack[1];
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299 | var second = interpreter.StringStack.Top;
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300 | interpreter.StringStack.Remove(2);
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301 |
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302 | interpreter.BooleanStack.Push(first.IndexOf(second, StringComparison.Ordinal) >= 0);
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303 | return true;
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304 | }
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305 | }
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306 |
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307 | /// <summary>
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308 | /// True if the top char is in the top string
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309 | /// </summary>
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310 | [PushExpression(StackTypes.String, "STRING.CONTAINSCHAR", StackTypes.Boolean | StackTypes.Char)]
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311 | public class StringContainsCharExpression : StatelessExpression {
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312 | public override bool Eval(IInternalPushInterpreter interpreter) {
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313 | if (interpreter.StringStack.IsEmpty ||
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314 | interpreter.CharStack.IsEmpty)
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315 | return false;
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316 |
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317 | var str = interpreter.StringStack.Pop();
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318 | var c = interpreter.CharStack.Pop();
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319 |
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320 | interpreter.BooleanStack.Push(str.IndexOf(c) >= 0);
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321 | return true;
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322 | }
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323 | }
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324 |
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325 | /// <summary>
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326 | /// Puts on the integer stack the index of the top char in the top string
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327 | /// </summary>
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328 | [PushExpression(StackTypes.String, "STRING.INDEXOFCHAR", StackTypes.Integer | StackTypes.Char)]
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329 | public class StringIndexOfCharExpression : StatelessExpression {
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330 | public override bool Eval(IInternalPushInterpreter interpreter) {
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331 | if (interpreter.StringStack.IsEmpty ||
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332 | interpreter.CharStack.IsEmpty)
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333 | return false;
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334 |
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335 | var str = interpreter.StringStack.Pop();
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336 | var c = interpreter.CharStack.Pop();
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337 |
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338 | interpreter.IntegerStack.Push(str.IndexOf(c));
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339 | return true;
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340 | }
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341 | }
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342 |
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343 | /// <summary>
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344 | /// The number of times the top char is in the top string
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345 | /// </summary>
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346 | [PushExpression(StackTypes.String, "STRING.OCCURENCESOFCHAR", StackTypes.Integer | StackTypes.Char)]
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347 | public class StringOccurrencesOfCharExpression : StatelessExpression {
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348 | public override bool Eval(IInternalPushInterpreter interpreter) {
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349 | if (interpreter.StringStack.IsEmpty ||
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350 | interpreter.CharStack.IsEmpty)
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351 | return false;
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352 |
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353 | var str = interpreter.StringStack.Pop();
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354 | var c = interpreter.CharStack.Pop();
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355 |
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356 | var count = 0;
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357 | for (var i = 0; i < str.Length; i++)
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358 | if (str[i] == c) count++;
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359 |
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360 | interpreter.IntegerStack.Push(count);
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361 | return true;
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362 | }
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363 | }
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364 |
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365 | /// <summary>
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366 | /// In third string on stack, replaces second string with first string
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367 | /// </summary>
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368 | [PushExpression(StackTypes.String, "STRING.REPLACE")]
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369 | public class StringReplaceExpression : StatelessExpression {
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370 | public override bool Eval(IInternalPushInterpreter interpreter) {
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371 | if (interpreter.StringStack.Count < 3)
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372 | return false;
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373 |
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374 | var first = interpreter.StringStack[1];
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375 | var second = interpreter.StringStack.Top;
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376 | interpreter.StringStack.Remove(2);
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377 |
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378 | if (first.Length == 0 || second.Length == 0)
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379 | interpreter.StringStack.SetTop(first);
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380 | else {
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381 | var result = first.Replace(second, interpreter.StringStack.Top);
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382 | interpreter.StringStack.SetTop(result);
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383 | }
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384 |
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385 | return true;
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386 | }
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387 | }
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388 |
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389 | /// <summary>
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390 | /// In third string on stack, replaces first occurence of second string with first string
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391 | /// </summary>
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392 | [PushExpression(StackTypes.String, "STRING.REPLACEFIRST")]
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393 | public class StringReplaceLastExpression : StatelessExpression {
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394 | public override bool Eval(IInternalPushInterpreter interpreter) {
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395 | if (interpreter.StringStack.Count < 3)
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396 | return false;
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397 |
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398 | var first = interpreter.StringStack[0];
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399 | var second = interpreter.StringStack[1];
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400 | var third = interpreter.StringStack[2];
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401 | interpreter.StringStack.Remove(2);
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402 |
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403 | var result = ReplaceFirst(third, second, first);
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404 | interpreter.StringStack.SetTop(result);
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405 | return true;
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406 | }
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407 |
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408 | private static string ReplaceFirst(string text, string search, string replace) {
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409 | int pos = text.IndexOf(search);
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410 | if (pos < 0) {
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411 | return text;
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412 | }
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413 | return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
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414 | }
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415 | }
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416 |
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417 | /// <summary>
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418 | /// In top string on stack, replaces all occurences of second char with first char
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419 | /// </summary>
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420 | [PushExpression(StackTypes.String, "STRING.REPLACECHAR", StackTypes.Char)]
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421 | public class StringReplaceCharExpression : StatelessExpression {
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422 | public override bool Eval(IInternalPushInterpreter interpreter) {
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423 | if (interpreter.StringStack.IsEmpty ||
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424 | interpreter.CharStack.Count < 2)
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425 | return false;
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426 |
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427 | var first = interpreter.CharStack[1];
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428 | var second = interpreter.CharStack.Top;
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429 | interpreter.CharStack.Remove(2);
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430 |
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431 | var result = interpreter.StringStack.Top.Replace(first, second);
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432 | interpreter.StringStack.SetTop(result);
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433 | return true;
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434 | }
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435 | }
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436 |
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437 | /// <summary>
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438 | /// In top string on stack, replaces first occurence of second char with first char
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439 | /// </summary>
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440 | [PushExpression(StackTypes.String, "STRING.REPLACEFIRSTCHAR", StackTypes.Char)]
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441 | public class StringReplaceLastCharExpression : StatelessExpression {
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442 | public override bool Eval(IInternalPushInterpreter interpreter) {
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443 | if (interpreter.StringStack.IsEmpty ||
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444 | interpreter.CharStack.Count < 2)
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445 | return false;
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446 |
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447 | var str = interpreter.StringStack.Top;
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448 | var first = interpreter.CharStack[1];
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449 | var second = interpreter.CharStack.Top;
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450 | interpreter.CharStack.Remove(2);
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451 |
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452 | var pos = str.IndexOf(first);
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453 |
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454 | if (pos < 0)
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455 | return true;
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456 |
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457 | var result = str.Substring(0, pos) +
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458 | second +
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459 | str.Substring(Math.Min(pos + 2, str.Length - 1));
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460 |
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461 | interpreter.StringStack.SetTop(result);
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462 | return true;
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463 | }
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464 | }
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465 |
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466 | /// <summary>
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467 | /// In top string on stack, remove all occurences of char
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468 | /// </summary>
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469 | [PushExpression(StackTypes.String, "STRING.REMOVECHAR", StackTypes.Char)]
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470 | public class StringRemoveCharExpression : StatelessExpression {
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471 | public override bool Eval(IInternalPushInterpreter interpreter) {
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472 | if (interpreter.StringStack.IsEmpty ||
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473 | interpreter.CharStack.IsEmpty)
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474 | return false;
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475 |
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476 | var c = interpreter.CharStack.Pop();
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477 | var result = interpreter.StringStack.Top.Trim(c);
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478 | interpreter.StringStack.SetTop(result);
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479 | return true;
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480 | }
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481 | }
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482 |
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483 | /// <summary>
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484 | /// Returns a function that sets char at index in string
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485 | /// </summary>
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486 | [PushExpression(StackTypes.String, "STRING.SETCHAR", StackTypes.Char | StackTypes.Integer)]
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487 | public class StringSetCharExpression : StatelessExpression {
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488 | public override bool Eval(IInternalPushInterpreter interpreter) {
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489 | if (interpreter.StringStack.IsEmpty ||
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490 | interpreter.CharStack.IsEmpty ||
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491 | interpreter.IntegerStack.IsEmpty)
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492 | return false;
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493 |
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494 | var str = interpreter.StringStack.Top;
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495 | var i = (int)interpreter.IntegerStack.Pop();
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496 | var c = interpreter.CharStack.Pop();
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497 |
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498 | if (str.Length == 0) {
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499 | interpreter.StringStack.Pop();
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500 | return true;
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501 | }
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502 |
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503 | var pos = str.Length == 1 ? 0 : Math.Abs(i) % (str.Length - 1);
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504 | var result = str.Substring(0, pos) + c + str.Substring(Math.Min(pos + 2, str.Length - 1));
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505 |
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506 | interpreter.StringStack.SetTop(result);
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507 | return true;
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508 | }
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509 | }
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510 | }
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