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POScala-IDE - object `apply` methods with different signatures get mixed?
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copied!<p>The code:</p> <pre><code>object Link { //TYPE-1 (purely functional) def apply(name: String, target: Page, f: () => Unit, isExclusive: Boolean) = new Link(name, target, f, isExclusive) //.. //TYPE-2 (purely side-effect) def apply(source: Page, target: Page, f: () => Unit, isExclusive: Boolean): Link = { val link = Link("LINK [" + source.getName + "]->[" + target.getName + "]", target, f, isExclusive) source += link link } //type-2 too def apply(source: Page, target: Page, isExclusive: Boolean): Link = Link (source, target, () => Unit, isExclusive) } </code></pre> <p>The explanation: there are two types of <code>apply</code> methods - the type-1 simply returns what companion class constructor returns, and the type-2 does not return anything, instead it just does something with the new instance. Thus the two different sets of arguments for them. However, I get the error (see the bottom of the post) on the <em>second</em> type-2 apply method where the <code>_Link_</code> is marked with the underscores:</p> <pre><code> def apply(source: Page, target: Page, isExclusive: Boolean): Link = _Link_ (source, target, () => Unit, isExclusive) </code></pre> <p>The first type-2 apply method does some job and in the second (and 3rd and 4th...) type-2 apply methods I want to just refer to the first one, instead of duplicating what is written there. However, Scala-IDE does not allow me to do this <em>unless</em> all the apply methods of type-1 are commented out. Seems like that Scala-IDE gets lost among the signatures and can't see my obvious intent. Or am I doing something wrong?</p> <p>The error: the second <code>apply</code> method shows an error which reads:</p> <blockquote> <p>overloaded method value apply with alternatives: (source: org.app.Page,target: org.app.Page,f: () => Unit,isExclusive: Boolean)org.app.meta.Link < and> (name: String,target: org.app.Page,f: () => Unit,isExclusive: Boolean)org.app.meta.Link cannot be applied to (org.app.Page, org.app.Page, () => Unit.type, Boolean)</p> </blockquote> <p><strong>UPDATE</strong></p> <p>Please note that the type-1 apply method is called without problems from the first type-2 one.</p>

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