12.3.3.24 || expressions For an expression expr of the form expr-first || expr-second: ?The definite assignment state of v before expr-first is the same as the definite assignment state of v before expr. ?The definite assignment state of v before expr-second is definitely assigned if the state of v after expr-first is either definitely assigned or .definitely assigned after false expression.. Otherwise, it is not definitely assigned. ?The definite assignment statement of v after expr is determined by: o If the state of v after expr-first is definitely assigned, then the state of v after expr is definitely assigned. o Otherwise, if the state of v after expr-second is definitely assigned, and the state of v after expr-first is .definitely assigned after true expression., then the state of v after expr is definitely assigned. Chapter 12 Variables 111 o Otherwise, if the state of v after expr-second is definitely assigned or .definitely assigned after false expression., then the state of v after expr is .definitely assigned after false expression.. o Otherwise, if the state of v after expr-first is .definitely assigned after true expression., and the state of v after expr-second is .definitely assigned after true expression., then the state of v after expr is .definitely assigned after true expression.. o Otherwise, the state of v after expr is not definitely assigned. [Example: In the example class A { static void G(int x, int y) { int i; if (x >= 0 || (i = y) >= 0) { // i not definitely assigned } else { // i definitely assigned } // i not definitely assigned } } the variable i is considered definitely assigned in one of the embedded statements of an if statement but not in the other. In the if statement in method G, the variable i is definitely assigned in the second embedded statement because execution of the expression (i = y) always precedes execution of this embedded statement. In contrast, the variable i is not definitely assigned in the first embedded statement, since x >= 0 might have tested true, resulting in the variable i抯 being unassigned. end example]
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