ECMA-334: 12.3.3.14 Try-finally statements

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C# Language Specification

12. Variables 12.3 Definite assignment 12.3.3 Precise rules for determining definite assignment 12.3.3.1 General rules for statements 12.3.3.2 Block statements, checked, and unchecked statements 12.3.3.3 Expression statements 12.3.3.4 Declaration statements 12.3.3.5 If statements 12.3.3.6 Switch statements 12.3.3.7 While statements 12.3.3.8 Do statements 12.3.3.9 For statements 12.3.3.10 Break, continue, and goto statements 12.3.3.11 Throw statements 12.3.3.12 Return statements 12.3.3.13 Try-catch statements 12.3.3.14 Try-finally statements 12.3.3.15 Try-catch-finally statements 12.3.3.16 Foreach statements 12.3.3.17 Using statements 12.3.3.18 Lock statements 12.3.3.19 General rules for simple expressions 12.3.3.20 General rules for expressions with embedded expressions 12.3.3.21 Invocation expressions and object creation expressions 12.3.3.22 Simple assignment expressions 12.3.3.23 && expressions 12.3.3.24 || expressions 12.3.3.25 ! expressions 12.3.3.26 ?: expressions 12.3.3.27 Anonymous method expressions 12.3.3.28 Yield statements 12.3.3.29 ?? expressions

© 2006 ECMA International

12.3.3.14 Try-finally statements

For a try statement stmt of the form:

try try-block finally finally-block

• The definite assignment state of v at the beginning of try-block is the same as the definite assignment state of v at the beginning of stmt.

• The definite assignment state of v at the beginning of finally-block is the same as the definite assignment state of v at the beginning of stmt.

• The definite assignment state of v at the end-point of stmt is definitely assigned if (and only if) either:

• v is definitely assigned at the end-point of try-block

• v is definitely assigned at the end-point of finally-block

If a control flow transfer (such as a goto statement) is made that begins within try-block, and ends outside of try-block, then v is also considered definitely assigned on that control flow transfer if v is definitely assigned at the end-point of finally-block. (This is not an only if—if v is definitely assigned for another reason on this control flow transfer, then it is still considered definitely assigned.)