ADDITIONAL SYSTEM INFORMATION :
Windows 10 22H2 (OS Build 19045.3324), JDK 21 (Oracle Corporation 21+35-2513)
jshell --enable-preview
A DESCRIPTION OF THE PROBLEM :
JEP 443 allows using an underscore (_) as an unnamed pattern when matching a record or for an unnamed exception, loop variable, resource in try-with-resources, etc.
However, JShell will not accept a line with an identifier of a single underscore. For instance, when entering this code:
int parseIntOrDefault(String value, int radix, int dflt) {
try {
return Integer.parseInt(value, radix);
} catch (NumberFormatException _) {
At this point, JShell prints:
| Error:
| reached end of file while parsing
and returns to the prompt. If the method is entered using, say, e as the name of the variable for the exception, JShell will accept it and it is then possible to up arrow, go back, replace 'e' with '_', and save the function. Something in parsing the code will not accept underscore line-by-line in incomplete code, but will accept it for a complete method or class.
STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Attempt to type the code below into JShell (started by jshell --enable-preview).
EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The code is accepted and the method is created.
ACTUAL -
| Error:
| reached end of file while parsing
---------- BEGIN SOURCE ----------
int parseIntOrDefault(String value, int radix, int dflt) {
try {
return Integer.parseInt(value, radix);
} catch (NumberFormatException _) {
return dflt;
}
}
---------- END SOURCE ----------
CUSTOMER SUBMITTED WORKAROUND :
Use an identifier, complete entering the code, then go back with up arrow or /edit and modify it to use underscore, the unnamed pattern.
FREQUENCY : always
Windows 10 22H2 (OS Build 19045.3324), JDK 21 (Oracle Corporation 21+35-2513)
jshell --enable-preview
A DESCRIPTION OF THE PROBLEM :
JEP 443 allows using an underscore (_) as an unnamed pattern when matching a record or for an unnamed exception, loop variable, resource in try-with-resources, etc.
However, JShell will not accept a line with an identifier of a single underscore. For instance, when entering this code:
int parseIntOrDefault(String value, int radix, int dflt) {
try {
return Integer.parseInt(value, radix);
} catch (NumberFormatException _) {
At this point, JShell prints:
| Error:
| reached end of file while parsing
and returns to the prompt. If the method is entered using, say, e as the name of the variable for the exception, JShell will accept it and it is then possible to up arrow, go back, replace 'e' with '_', and save the function. Something in parsing the code will not accept underscore line-by-line in incomplete code, but will accept it for a complete method or class.
STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Attempt to type the code below into JShell (started by jshell --enable-preview).
EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
The code is accepted and the method is created.
ACTUAL -
| Error:
| reached end of file while parsing
---------- BEGIN SOURCE ----------
int parseIntOrDefault(String value, int radix, int dflt) {
try {
return Integer.parseInt(value, radix);
} catch (NumberFormatException _) {
return dflt;
}
}
---------- END SOURCE ----------
CUSTOMER SUBMITTED WORKAROUND :
Use an identifier, complete entering the code, then go back with up arrow or /edit and modify it to use underscore, the unnamed pattern.
FREQUENCY : always