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Chapter ‎18   Unsafe code

conditional-expression: conditional-or-expression conditional-or-expression   ?   expression   :   expression

A conditional expression of the form b ? x : y first evaluates the condition b. Then, if b is true, x is evaluated and becomes the result of the operation. Otherwise, y is evaluated and becomes the result of the operation. A conditional expression never evaluates both x and y.

The conditional operator is right-associative, meaning that operations are grouped from right to left. For example, an expression of the form a ? b : c ? d : e is evaluated as a ? b : (c ? d : e).

The first operand of the ?: operator must be an expression of a type that can be implicitly converted to bool, or an expression of a type that implements operator true. If neither of these requirements is satisfied, a compile-time error occurs.

The second and third operands of the ?: operator control the type of the conditional expression. Let X and Y be the types of the second and third operands. Then,

If X and Y are the same type, then this is the type of the conditional expression.

Otherwise, if an implicit conversion (§‎6.1) exists from X to Y, but not from Y to X, then Y is the type of the conditional expression.

Otherwise, if an implicit conversion (§‎6.1) exists from Y to X, but not from X to Y, then X is the type of the conditional expression.

Otherwise, no expression type can be determined, and a compile-time error occurs.

The run-time processing of a conditional expression of the form b ? x : y consists of the following steps:

First, b is evaluated, and the bool value of b is determined:

If an implicit conversion from the type of b to bool exists, then this implicit conversion is performed to produce a bool value.

Otherwise, the operator true defined by the type of b is invoked to produce a bool value.

If the bool value produced by the step above is true, then x is evaluated and converted to the type of the conditional expression, and this becomes the result of the conditional expression.

Otherwise, y is evaluated and converted to the type of the conditional expression, and this becomes the result of the conditional expression.

7.13 Assignment operators

The assignment operators assign a new value to a variable, a property, an event, or an indexer element.

assignment: unary-expression   assignment-operator   expression

assignment-operator:  one of =   +=   -=   *=   /=   %=   &=   |=   ^=   <<=   >>=

The left operand of an assignment must be an expression classified as a variable, a property access, an indexer access, or an event access.

The = operator is called the simple assignment operator. It assigns the value of the right operand to the variable, property, or indexer element given by the left operand. The left operand of the simple assignment operator may not be an event access (except as described in §‎10.7.1). The simple assignment operator is described in §‎7.13.1.

The assignment operators other than the = operator are called the compound assignment operators. These operators perform the indicated operation on the two operands, and then assign the resulting value to the

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