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2 |
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5 |
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6 |
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7 |
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8 |
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9 | const Observer = {
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10 |
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11 | splice () {
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12 | const self = this;
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13 |
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14 | let startIndex = arguments[0];
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15 | let deleteCount = arguments[1];
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16 | let addCount = arguments.length > 2 ? arguments.length - 2 : 0;
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17 |
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18 | if (typeof startIndex !== 'number' || typeof deleteCount !== 'number') {
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19 | return [];
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20 | }
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21 |
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22 |
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23 | if (startIndex < 0) {
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24 | startIndex = self.length + startIndex;
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25 | startIndex = startIndex > 0 ? startIndex : 0;
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26 | } else {
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27 | startIndex = startIndex < self.length ? startIndex : self.length;
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28 | }
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29 |
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30 |
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31 | if (deleteCount < 0) {
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32 | deleteCount = 0;
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33 | } else if (deleteCount > (self.length - startIndex)) {
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34 | deleteCount = self.length - startIndex;
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35 | }
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36 |
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37 | let totalCount = self.$meta.length;
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38 | let argumentIndex = 2;
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39 | let argumentsCount = arguments.length - argumentIndex;
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40 | const result = self.slice(startIndex, deleteCount);
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41 |
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42 | let updateCount = (totalCount - 1) - startIndex;
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43 |
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44 | const promises = [];
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45 |
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46 | const length = self.length + addCount - deleteCount;
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47 |
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48 | if (self.length !== length) {
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49 | promises.push(self.$meta.listener.bind(null, self, self.$meta.path.slice(0, -1), 'length'));
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50 | }
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51 |
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52 | if (updateCount > 0) {
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53 | let value;
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54 | let index = startIndex;
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55 |
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56 | while (updateCount--) {
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57 | const key = index++;
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58 |
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59 | if (argumentsCount && argumentIndex < argumentsCount) {
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60 | value = arguments[argumentIndex++];
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61 | } else {
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62 | value = self.$meta[index];
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63 | }
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64 |
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65 | self.$meta[key] = Observer.create(value, self.$meta.listener, self.$meta.path + key);
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66 | promises.push(self.$meta.listener.bind(null, self.$meta[key], self.$meta.path + key, key));
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67 | }
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68 |
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69 | }
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70 |
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71 |
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72 | if (addCount > 0) {
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73 | while (addCount--) {
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74 | const key = self.length;
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75 |
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76 | if (key in this === false) {
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77 | Object.defineProperty(this, key, Observer.descriptor(key));
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78 | }
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79 |
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80 | self.$meta[key] = Observer.create(arguments[argumentIndex++], self.$meta.listener, self.$meta.path + key);
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81 | promises.push(self.$meta.listener.bind(null, self.$meta[key], self.$meta.path + key, key));
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82 |
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83 | }
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84 | }
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85 |
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86 | if (deleteCount > 0) {
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87 | while (deleteCount--) {
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88 | self.$meta.length--;
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89 | self.length--;
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90 | const key = self.length;
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91 | promises.push(self.$meta.listener.bind(null, undefined, self.$meta.path + key, key));
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92 | }
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93 | }
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94 |
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95 | Promise.resolve().then(function () {
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96 | promises.reduce(function (promise, item) {
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97 | return promise.then(item);
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98 | }, Promise.resolve());
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99 | }).catch(console.error);
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100 |
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101 | return result;
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102 | },
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103 |
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104 | arrayProperties () {
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105 | const self = this;
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106 |
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107 | return {
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108 | push: {
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109 | value: function () {
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110 | if (!arguments.length) return this.length;
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111 |
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112 | for (let i = 0, l = arguments.length; i < l; i++) {
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113 | self.splice.call(this, this.length, 0, arguments[i]);
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114 | }
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115 |
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116 | return this.length;
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117 | }
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118 | },
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119 | unshift: {
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120 | value: function () {
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121 | if (!arguments.length) return this.length;
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122 |
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123 | for (let i = 0, l = arguments.length; i < l; i++) {
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124 | self.splice.call(this, 0, 0, arguments[i]);
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125 | }
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126 |
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127 | return this.length;
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128 | }
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129 | },
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130 | pop: {
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131 | value: function () {
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132 | if (!this.length) return;
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133 | const result = self.splice.call(this, this.length-1, 1);
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134 | return result[0];
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135 | }
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136 | },
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137 | shift: {
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138 | value: function () {
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139 | if (!this.length) return;
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140 | const result = self.splice.call(this, 0, 1);
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141 | return result[0];
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142 | }
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143 | },
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144 | splice: {
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145 | value: self.splice
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146 | }
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147 | };
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148 | },
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149 |
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150 | objectProperties () {
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151 | const self = this;
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152 |
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153 | return {
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154 | $get: {
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155 | value: function (key) {
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156 | return this.$meta[key];
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157 | }
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158 | },
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159 | $set: {
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160 | value: function (key, value) {
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161 | if (value !== this.$meta[key]) {
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162 |
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163 | if (key in this === false) {
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164 | Object.defineProperty(this, key, self.descriptor(key));
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165 | }
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166 |
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167 | this.$meta[key] = self.create(value, this.$meta.listener, this.$meta.path + key);
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168 | this.$meta.listener(this.$meta[key], this.$meta.path + key, key, this);
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169 | }
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170 | }
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171 | },
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172 | $remove: {
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173 | value: function (key) {
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174 | if (key in this) {
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175 | if (this.constructor === Array) {
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176 | return self.splice.call(this, key, 1);
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177 | } else {
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178 | let result = this[key];
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179 | delete this.$meta[key];
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180 | delete this[key];
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181 | this.$meta.listener(undefined, this.$meta.path + key, key);
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182 | return result;
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183 | }
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184 | }
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185 | }
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186 | }
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187 | };
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188 | },
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189 |
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190 | descriptor (key) {
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191 | const self = this;
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192 |
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193 | return {
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194 | enumerable: true,
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195 | configurable: true,
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196 | get: function () {
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197 | return this.$meta[key];
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198 | },
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199 | set: function (value) {
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200 | if (value !== this.$meta[key]) {
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201 | this.$meta[key] = self.create(value, this.$meta.listener, this.$meta.path + key);
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202 | this.$meta.listener(this.$meta[key], this.$meta.path + key, key, this);
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203 | }
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204 | }
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205 | };
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206 | },
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207 |
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208 | create (source, listener, path) {
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209 |
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210 |
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211 | if (!source || source.constructor !== Object && source.constructor !== Array) {
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212 | return source;
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213 | }
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214 |
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215 | path = path ? path + '.' : '';
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216 |
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217 | const type = source.constructor;
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218 | const target = source.constructor();
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219 | const descriptors = {};
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220 |
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221 | descriptors.$meta = {
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222 | value: source.constructor()
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223 | };
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224 |
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225 | descriptors.$meta.value.path = path;
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226 | descriptors.$meta.value.listener = listener;
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227 |
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228 | if (type === Array) {
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229 | for (let key = 0, length = source.length; key < length; key++) {
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230 | descriptors.$meta.value[key] = this.create(source[key], listener, path + key);
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231 | descriptors[key] = this.descriptor(key);
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232 | }
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233 | }
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234 |
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235 | if (type === Object) {
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236 | for (let key in source) {
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237 | descriptors.$meta.value[key] = this.create(source[key], listener, path + key);
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238 | descriptors[key] = this.descriptor(key);
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239 | }
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240 | }
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241 |
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242 | Object.defineProperties(target, descriptors);
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243 | Object.defineProperties(target, this.objectProperties(source, listener, path));
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244 |
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245 | if (type === Array) {
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246 | Object.defineProperties(target, this.arrayProperties(source, listener, path));
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247 | }
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248 |
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249 | return target;
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250 | }
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251 |
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252 | };
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253 |
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254 | export default Observer;
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