Javascript split can keep splitted value?

Question

In Javascript :

var myString = \"This is my string\";

console.log(myString.split(/(\\s)/));

Output : [\"This\", \" \", \"is\", \" \"

Answer 1

The two regexs you're using are only slightly different.

/(\s)/ has a capture group of \s, so when used with split() it will add the anything found in the capture group to the array.

The regex /\s/ has no capture group, so split() ignores the matches and does not add them to the array.

Similarly, if you execute:

var myString = "This is my string";

console.log(myString.split(/(my)/));  //includes matched capture group in results
console.log(myString.split(/my/));  //ignores matches

Will output:

["This is ", "my", " string"]
["This is ", " string"]

Hope that helps!