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setbit(+Number, +Index, -Result)

Result is Number with the Index'th bit set.
Number
Integer.
Index
Non-negative integer.
Result
Output: integer.

Description

Set the Index'th bit in Number giving Result. The least significant bit has index zero. Two's complement representation is assumed. This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to setbit(Number, Index, Result) is equivalent to 
    Result is setbit(Number, Index)
which should be preferred.

In coroutining mode, if Number or Index are uninstantiated, the call is delayed until these variables are instantiated.

Modes and Determinism

Exceptions

(4) instantiation fault
Number or Index is not instantiated (non-coroutining mode only).
(5) type error
Number or Index is a number but not an integer.
(24) number expected
Number or Index is not of a numeric type.

Examples

    Result is setbit(0, 3).		% gives Result = 8
    Result is setbit(1, 8).		% gives Result = 257
    Result is setbit(setbit(0,3),5).	% gives Result = 40

See Also

is / 2, clrbit / 3, getbit / 3