java - While(false) causes unreachable statement compilation error -

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i removing block of code our code base before release , used if(false) statement prevent execution:

if (false) {     arraylist<string> list = new arraylist<string>();     ... }

this compiles fine , prevent execution of offending block of code (right or wrong, that's not current argument).

however, kind of accident, changed block above to:

while (false) {     arraylist<string> list = new arraylist<string>();     ... }

and received unreachable statement compilation error.

i appreciate compilation error , understand reasons, however, i'm struggling comprehend difference between 2 blocks , why former compiles fine latter not when both have unreachable statements.

in both case compiler should raise error, because code between braces pointless, but if (false) kept in java simulate c/c++ preprocessor #if 0, quite common way of disabling parts of code testing or debugging.

edit: reference, "conditional compiling" detailed @ end of chapter 14.21 of java language specification.


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