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function defaultToString(item) {
if (item === null) {
return 'NULL';
} if (item === undefined) {
return 'UNDEFINED';
} if (typeof item === 'string' || item instanceof String) {
return `${item}`;
}
return item.toString();
}
class Dictionary {
constructor(toStrFn = defaultToString) {
this.toStrFn = toStrFn;
this.table = {};
}
set(key, value) {
if (key != null && value != null) {
const tableKey = this.toStrFn(key);
this.table[tableKey] = new ValuePair(key, value);
return true;
}
return false;
}
get(key) {
const valuePair = this.table[this.toStrFn(key)];
return valuePair == null ? undefined : valuePair.value;
}
hasKey(key) {
return this.table[this.toStrFn(key)] != null;
}
remove(key) {
if (this.hasKey(key)) {
delete this.table[this.toStrFn(key)];
return true;
}
return false;
}
values() {
return this.keyValues().map(valuePair => valuePair.value);
}
keys() {
return this.keyValues().map(valuePair => valuePair.key);
}
keyValues() {
return Object.values(this.table);
}
forEach(callbackFn) {
const valuePairs = this.keyValues();
for (let i = 0; i < valuePairs.length; i++) {
const result = callbackFn(valuePairs[i].key, valuePairs[i].value);
if (result === false) {
break;
}
}
}
isEmpty() {
return this.size() === 0;
}
size() {
return Object.keys(this.table).length;
}
clear() {
this.table = {};
}
toString() {
if (this.isEmpty()) {
return '';
}
const valuePairs = this.keyValues();
let objString = `${valuePairs[0].toString()}`;
for (let i = 1; i < valuePairs.length; i++) {
objString = `${objString},${valuePairs[i].toString()}`;
}
return objString;
}
}
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