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https://issues.apache.org/jira/browse/GROOVY-10223?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17558556#comment-17558556
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ASF GitHub Bot commented on GROOVY-10223:
-----------------------------------------
eric-milles commented on PR #1732:
URL: https://github.com/apache/groovy/pull/1732#issuecomment-1165715088
You can also do this, but I don't think it is an improvement over
"optional.map(String::length).orElse(null)" or
"optional.orElse(null)?.length()":
```groovy
def nothing = Optional.empty(), something = Optional.of('foo')
def value = nothing*.length()?[0]
assert value == null
value = something*.length()?[0]
assert value == 3
```
> Add support for Optional to DefaultTypeTransformation.asCollection()
> --------------------------------------------------------------------
>
> Key: GROOVY-10223
> URL: https://issues.apache.org/jira/browse/GROOVY-10223
> Project: Groovy
> Issue Type: New Feature
> Components: groovy-jdk
> Reporter: Stephen Smith
> Assignee: Eric Milles
> Priority: Trivial
> Labels: features
>
> The JDK recently added support for *Optional::stream()* which returns a
> stream containing either the unwrapped value or an empty stream if the
> *Optional* is empty.
> In the groovy-jdk, using iteration however will call
> {noformat}
> DefaultTypeTransformation.asCollection(){noformat}
> which does not specifically check for type *Optional*, instead it will just
> wrap the *Optional* itself in a *List* rather than the unwrapped value as the
> default behavior.
> Adding an _if else_ clause will allow using the Optional as either a single
> or empty list.
> {code:java}
> if (value instanceOf Optional) {
> return ((Optional)value).map(List::of).orElse(List.of())
> }{code}
> Alternatively, add an *asList()* to the Optional class.
> (edit: 2021-09-13, missing bracket in code example)
>
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