downs wrote:
> Qian Xu wrote:
>> Hi All,
>>
>> Is minimal evaluation always enabled in D?
>>
>> I want to write a function IsNull(), so that I can check the precondition as
>> follows:
>>
>> if (isNull(foo) ||
>> isNull(foo.getBar) ||
>> isNull(foo.getBar.getBar2)
>> {
>> return false;
>> }
>> // normal code goes here
>>
>> If an argument is null, the IsNull() will return false. Internally it will
>> be logged to console as well.
>>
>> But I am not sure, if dmd-compiler generates code without minimal evaluation
>> in some cases. If minimal evaluation is not always enabled. I cannot do
>> precodition check in my way.
>>
>> --Qian
>
> Short-circuit evaluation is always enabled.
>
> http://digitalmars.com/d/1.0/expression.html#OrOrExpression
>
> "If the left operand, converted to type bool, evaluates to true, then the
> right operand is not evaluated."
You beat me to it, AND you found it in the spec.
?cookie downs
-- Daniel
