Databases
StackOverflow2013
Postsdbo
POconditional loop conversion in Scala
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POconditional loop conversion in Scala
    primarykey
    data
    text
    <p>I'd like to convert a piece of Java code which looks like the following into Scala:</p> <pre><code>for (Iterator&lt;Task&gt; it = tasks.iterator(); it.hasNext() &amp;&amp; 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 =&gt; workflow.isAutoRun &amp;&amp; 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 =&gt; Boolean): Boolean = { var res = true while (res &amp;&amp; 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 =&gt; !isAutoRun || !runTask(t))</code></p> </blockquote>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USoxbow_lakes
    1. USoxbow_lakes
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POconditional loop conversion in Scala
      1. USoxbow_lakes
      1. VTFavorite
    2. VO
      singulars
      1. POconditional loop conversion in Scala
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POconditional loop conversion in Scala
      1. USVonC
      1. VTFavorite
    1. COWhere's `workflow.isAutoRun` coming from? Does it change its value because of a side effect of running the tasks?
      singulars
      1. POconditional loop conversion in Scala
      1. USDaniel C. Sobral
    2. CO@Daniel - yes: its value may change over time although it is independent of task success/failure. Basically a user can change a workflow to put it in *manual* state, ensuring that this code will not attempt to complete the workflow. This is a legacy app (the `isAutoRun` results in a remote invocation) and cannot be modified
      singulars
      1. POconditional loop conversion in Scala
      1. USoxbow_lakes
    3. CO@Daniel - see my comments to *Yardena* below - I think the problem is that the legacy app I'm working with is obviously not functional in nature/style and hence doesn't fit easily with the naming of the collection manipulation methods
      singulars
      1. POconditional loop conversion in Scala
      1. USoxbow_lakes
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload