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https://issues.apache.org/jira/browse/GROOVY-7427?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Paul King updated GROOVY-7427:
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Component/s: xforms
> 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
> Components: xforms
> 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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