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william coleman
4,391 PointsDoes the automatic creation of the $3, $4, etc variable only happen in jshell?
Does the automatic creation of the $3, $4, etc variable only happen in jshell, or does it happen in other environments as well?
1 Answer
Tonnie Fanadez
UX Design Techdegree Graduate 22,796 PointsI haven't seen this in other environments apart from JShell itself.
In JShell $1,$2, $3, $4,$5, $100 etc. are called Positional Parameters. A positional parameter is a parameter denoted by one or more digits, other than the single digit 0.
Once Jshell has allocated a variable with a preceding dollar symbol followed by a digit, it means that you can use the value of this variable on Jshell by typing out the positional parameter.
For Example
If you type Integer.parseInt("17") JShell prints out $5==> 17
You can then use the created value by just typing "$5"
jshell> Integer.parseInt("17")
$5 ==> 17
// JShell creates a variable with a positional parameter denoted as $5 with a value of 17
jshell> int number = 3;
number ==> 3
jshell> number + $5 //---->>> You can use the Jshell value by just typing $5
$7 ==> 20
jshell>
william coleman
4,391 PointsThanks, Tonnie!
Tonnie Fanadez
UX Design Techdegree Graduate 22,796 PointsTonnie Fanadez
UX Design Techdegree Graduate 22,796 Pointswilliam coleman always welcome.