Re: Issue 3533 in pharo: add Dictionary>>at:ifAbsentValue:

>
> Comment #4 on issue 3533 by siguctua: add Dictionary>>at:ifAbsentValue:
> http://code.google.com/p/pharo/issues/detail?id=3533
>
> Of course, you can always use:
>
> dict at: x ifAbsent: y
>
> except that it is not always desirable to send #value message to 'y'
> argument, especially if you can't tell anything about nature of objects you
> are storing in dictionary, and when speed is essential, it would be good to
> have something like this:
>
> at: key ifAbsentValue: defaultValue
> "Answer the value associated with the key or, if key isn't found,
> answer the default value"
> ^((array at: (self findElementOrNil: key)) ifNil: [ ^
> defaultValue ]) value
>
>
> Cog VM shows a significant difference in delivering an answer:
>
> | dict |
> dict := Dictionary new.
> dict at: #a put: 1.
>
> [ 1000000 timesRepeat: [ dict at: #foo ifAbsentValue: #bar ] ] timeToRun
> 236 234 239
>
> [ 1000000 timesRepeat: [ dict at: #a ifAbsentValue: #bar ] ] timeToRun
> 241 234 236 237
>
> [ 1000000 timesRepeat: [ dict at: #foo ifAbsent: [#bar] ] ] timeToRun
> 322 318
>
> [ 1000000 timesRepeat: [ dict at: #a ifAbsent: [ #bar ] ] ] timeToRun
> 363 336  340