Convert Set to String

Option 1:

	Set<Id> accId = new Set<Id>();
	for(Account acc : [SELECT Id, Name FROM Account LIMIT 10]) {
	accId.add(acc.Id);
	}
	system.debug(accId);
	String str = ''+accId;
	system.debug(str);

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Drawback: once the set size increase above option to convert the set to string as it receives i.e.

Option 2:

	Set<Id> accId = new Set<Id>();
	for(Account acc : [SELECT Id, Name FROM Account LIMIT 100]) {
	accId.add(acc.Id);
	}
	List<Id> strList = new List<Id>(accId);
	system.debug('strList: ' + strList);
	String str = string.join(strList, ',');
	system.debug('String value : ' + str);

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output: