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How to check if an object is an array?
...r ];
}
Or if you're not concerned about performance, you could just do a concat to a new empty Array.
someVar = [].concat( someVar );
There's also the constructor which you can query directly:
if (somevar.constructor.name == "Array") {
// do something
}
Check out a thorough treatment f...
How to insert a character in a string at a certain position?
...
There is no loop, it's a simple concatenation case and compiler should optimize it using a string builder, for readability I prefer to use the + operator, there is no need in this case to use StringBuilder explicitly. Using "StringBuilder" solution because ...
How to do ToString for a possibly null object?
...nger than just "" + myObj. But I've read that creates extra strings. str.Concat(myObj) seems to work just fine and is "even faster".
– drzaus
Dec 1 '17 at 17:48
add a commen...
How can I combine two HashMap objects containing the same types?
...ual keys and values, so you'll need to use a loop or Map.forEach. Here we concatenate strings for duplicate keys:
map3 = new HashMap<>(map1);
for (Map.Entry<String, String> e : map2.entrySet())
map3.merge(e.getKey(), e.getValue(), String::concat);
//or instead of the above loop
map...
console.log timestamps in Chrome?
...
I convert arguments to Array using Array.prototype.slice so that I can concat with another Array of what I want to add, then pass it into console.log.apply(console, /*here*/);
var log = function () {
return console.log.apply(
console,
['['+new Date().toISOString().slice(11,-...
Logger slf4j advantages of formatting with {} instead of string concatenation
Is there any advantage of using {} instead of string concatenation?
5 Answers
5
...
How to change collation of database, table, column?
...ll tables to a certain type (utf8_general_ci in my example below).
SELECT concat
(
'ALTER TABLE ',
t1.TABLE_SCHEMA,
'.',
t1.table_name,
' MODIFY ',
t1.column_name,
' ',
...
Export/import jobs in Jenkins
...ttp://<USER>:<API_TOKEN>@OLD_JENKINS/crumbIssuer/api/xml?xpath=concat(//crumbRequestField,":",//crumb)')
$ CRUMB_NEW=$(curl -s 'http://<USER>:<API_TOKEN>@NEW_JENKINS/crumbIssuer/api/xml?xpath=concat(//crumbRequestField,":",//crumb)')
Apply crumb with -H CRUMB:
$ curl -s -H...
Using Java 8 to convert a list of objects into a string obtained from the toString() method
...ry:
String s = list.stream().map(e -> e.toString()).reduce("", String::concat);
Explanation: map converts Integer stream to String stream, then its reduced as concatenation of all the elements.
Note: This is normal reduction which performs in O(n2)
for better performance use a StringBuilder ...
Joining three tables using MySQL
...
SELECT
employees.id,
CONCAT(employees.f_name," ",employees.l_name) AS 'Full Name', genders.gender_name AS 'Sex',
depts.dept_name AS 'Team Name',
pay_grades.pay_grade_name AS 'Band',
designations.designation_name AS 'Role'
FROM employees
LE...