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
