X hits on this document

359 views

0 shares

159 / 396

C# LANGUAGE SPECIFICATION

large to represent in the destination type, z is an infinity with the same sign as x y.

y

+0

–0

+∞

–∞

NaN

x

z

x

x

–∞

+∞

NaN

+0

–y

+0

+0

–∞

+∞

NaN

–0

–y

–0

+0

–∞

+∞

NaN

+∞

+∞

+∞

+∞

NaN

+∞

NaN

–∞

–∞

–∞

–∞

–∞

NaN

NaN

NaN

NaN

NaN

NaN

NaN

NaN

NaN

Decimal subtraction:

decimal operator –(decimal x, decimal y);

If the resulting value is too large to represent in the decimal format, a System.OverflowException is thrown. The scale of the result, before any rounding, is the larger of the scales of the two operands.

Decimal subtraction is equivalent to using the subtraction operator of type System.Decimal.

Enumeration subtraction. Every enumeration type implicitly provides the following predefined operator, where E is the enum type, and U is the underlying type of E:

U operator –(E x, E y);

This operator is evaluated exactly as (U)((U)x (U)y). In other words, the operator computes the difference between the ordinal values of x and y, and the type of the result is the underlying type of the enumeration.

E operator –(E x, U y);

This operator is evaluated exactly as (E)((U)x y). In other words, the operator subtracts a value from the underlying type of the enumeration, yielding a value of the enumeration.

Delegate removal. Every delegate type implicitly provides the following predefined operator, where D is the delegate type:

D operator –(D x, D y);

The binary operator performs delegate removal when both operands are of some delegate type D. If the operands have different delegate types, a compile-time error occurs. If the first operand is null, the result of the operation is null. Otherwise, if the second operand is null, then the result of the operation is the value of the first operand. Otherwise, both operands represent invocation lists (§‎15.1) having one or more entries, and the result is a new invocation list consisting of the first operand’s list with the second operand’s entries removed from it, provided the second operand’s list is a proper contiguous sublist of the first’s. (To determine sublist equality, corresponding entries are compared as for the delegate equality operator (§‎7.9.8).)null. For example:

delegate void D(int x);

class C { public static void M1(int i) { /* … */ } public static void M2(int i) { /* … */ } }