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POconditional loop conversion in Scala
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copied!<p>I'd like to convert a piece of Java code which looks like the following into Scala:</p> <pre><code>for (Iterator<Task> it = tasks.iterator(); it.hasNext() && workflow.isAutoRun();) { Task task = it.next(); if (!runTask(task)) break; } </code></pre> <p>I am not a fan of the scala <code>for-</code>comprehensions (not that I know how to <em>break</em> the iteration anyway) and I've come up with the following:</p> <pre><code>val completed = tasks.forall { task => workflow.isAutoRun && runTask(task) } </code></pre> <p>However, the scaladoc for the <code>forall</code> method looks like the following (italics mine):</p> <blockquote> <p>Apply a predicate <code>p</code> <em>to all elements</em> of this iterable object and return true, iff the predicate yields true for all elements</p> </blockquote> <p>This is not equivalent to what I have done (because it implies that the predicate will be evaluated for each item, regardless of whether a previous evaluation has returned <code>false</code>) and (in fact) not actually equivalent to what the <code>forall</code> method actually does, which on <code>Iterator</code> looks like:</p> <pre><code> def forall(p: A => Boolean): Boolean = { var res = true while (res && hasNext) res = p(next) res } </code></pre> <p>Anyway, I digress: has anyone got any better suggestions for what the scala code should look like? I want to see something which conveys the intent better:</p> <blockquote> <p><code>tasks.doUntil(t => !isAutoRun || !runTask(t))</code></p> </blockquote>

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