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https://issues.apache.org/jira/browse/GROOVY-7427?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15151093#comment-15151093
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Christopher Smith commented on GROOVY-7427:
-------------------------------------------
Aha. A bit ironic for my use case (where all the fields are final), but
understandable. Looks like we'll just have to keep maintaining constructors
manually for the time being. Thanks for checking!
> TupleConstructor should allow a mechanism to switch off automatic parameter
> defaults
> ------------------------------------------------------------------------------------
>
> Key: GROOVY-7427
> URL: https://issues.apache.org/jira/browse/GROOVY-7427
> Project: Groovy
> Issue Type: Improvement
> Reporter: Paul King
> Assignee: Paul King
> Priority: Minor
> Fix For: 2.5.0-beta-1
>
>
> When using @TupleConstructor, it automatically provides defaults for the
> parameters. This is particularly useful behavior since it allows parameters
> which can remain as their default (user provided or null/0/false) can be left
> out of the constructor. In particular, a no-arg constructor corresponds to
> the case of all arguments left out. This is exactly the kind of constructor
> which Groovy needs for default named-argument processing.
> Having said that, there are times when all is required is a single simple
> constructor having all of the classes properties. This issue allows a
> parameter {{defaults=false}} to be set to enable this new behavior.
> For this class:
> {code}
> @TupleConstructor
> class Person {
> String first, last
> int age
> }
> {code}
> The following normal constructor is produced:
> {code}
> Person(String first=null, String last=null, int age=0) { this.first = first
> //etc... }
> {code}
> After Groovy's compilation phases are complete, the following constructors
> are visible to Java:
> {code}
> Person(String first, String last, int age) { //... }
> Person(String first, String last) { this(first, last, 0) }
> Person(String first) { this(first, null) }
> Person() { this(null) }
> {code}
> Adding {{defaults=false}} as a parameter to TupleConstructor means that just
> the first of these will be produced. If any of the properties has a default
> value, when this setting is made false, an error will be flagged.
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