Why is IntelliJ highlighting errors in one project, but not another? - scala

I'm using IntelliJ 13 and the Scala plugin. In one project if I make an obvious type error I get a visual indication, like this:
But I just started a new project and a similar thing is not highlighted, even after I compile.
I'm giving a presentation on some Scala code and I'd like it if the type errors highlighted like in the first one, but I have no idea where the setting is.

One reason could be that the level of highlighting is set to a lower setting. Check your lower right corner for a button which adjusts this setting with a slider. It looks like (at least to me) a policeman face :)
Another thing is that you might not have declared what additional languages you're using besides the primary one. You can configure this in the project settings.
Also if you are using a tool to build a project (like Maven for example) try rebuilding or reimporting your project.
edit: One last thing. Make sure IDEA isn'currently reindexing or running some background tasks, this really messes up code correction.

Related

Cannot run a Scala program in IntelliJ

So I made a project in Scala -> Activator. I am trying to run it but I cannot even select it, it has a main function. When I press the alt+shift+F10 nothing happens at all.
The icon for the main.scala file also has some red thing in the bottom right corner, which I'm unsure what that means.
Also if I edit the file there is no star at the filename, like if it was unchanged.
Answering rather than deleting this question. I solved the problem by creating a Maven project or by using sbt, it will not run right out of the gate like Java (coming from a Java background).

How do I prevent Eclipse (with pydev) from uncollapsing code?

I'm using Eclipse Kepler (4.3) (with pydev, in case that matters). If I collapse my code (using Ctrl-9 or the Source menu) and then selectively uncollapse only the part I'm working on, it works fine for a while. But at some point in the session, I'll notice that Eclipse has randomly (?) decided to uncollapse all the code. Am I doing something wrong, or is this a known "feature" of Eclipse? And is there any way to prevent it?
And in case there's no way to prevent this, I have a follow-up question: Is there any way to collapse just the code I have selected? I.e., can I select a set of functions and collapse them all at once rather than going through and collapsing them one at a time?

Eclipse working sets -- how to rename them? Also, can the error-icon be disabled?

After mild frustration with the difficulty to make top-level "plain old folders" within Eclipse for visual-organization purposes, I discovered that the thing I'm after is called a "working set". Hooray! But they don't seem to be rename-able, by any of the apparent avenues (right-clicking on it or using the Configure Working Sets window).
Is that just the way things are, since no one should be so lazy as to refuse making a new working set with the right name and transferring everything over? Or am I missing something obvious?
I also have a more minor question whose answer I already think I know. Can I tell a specific working set not to change its icon to have the "red X" when one of its children has an error? Nothing in the preferences under Debugging suggests to me the ability to turn off the automatic icon-changing. It's a useful feature, but I have a few simple practice projects with very basic errors, and I don't need the visual reminder to "fix" them, especially if they're in my "Practice" working set, whose icon I'd prefer not to change.
To rename a Working Set, you need to get to the dialogue of selecting a Working Set (click on the white down arrow at the top right of the package explorer > Configure Working Sets..), focus on your Working Set and click the "Edit" button. There, you can change the Working Set's name, as well as what's actually included in the Working Set.
There is no way (that I know of) to change the icon display to avoid showing the errors marker.

IntelliJ IDEA Scala plugin doesn't find errors

I've just tried IntelliJ IDEA 12 with the Scala plugin, but it doesn't find and highlight errors in my code. I can for example write arbitrary code in a method and it looks like everything is fine. Is IDEA not able to do this? Or do I have to configure something special?
IDEA's Scala plug-in is not equivalent to the compiler in type-checking your source code, but it does pretty well. The one thing you'll want to do (unless, perhaps, your hardware is not fairly current and high-performance) is turn on "Type-Aware Highlighting."
If you look in the lower-right-hand corner of the IDEA window (when you're editing a project with Scala enabled) you'll see one of two icons, both of which take the form of a square-bracketed bit of text. That text is either blank on a yellow background or the letter T on a green background. Clicking it toggles between those two states. When the green T is displayed, Type-Aware highlighting is on.
Give that a try.
Simply updating the plugin version could fix the problem. Old or install/initial plugins may not contain relevant support.
Determining Scala plugin version in Settings:

Creating an Eclipse plug-in to display content assist regardless of cursor location

I'm working on some reflection stuff using Java across XML files. The process would be made much faster and less prone to error if I could get content assist to behave like a tree in a small window off to the side, but more than by my current cursor location.
My question is can this really be done without reinventing the wheel too much? Essentially I want to display a list of classes, choose a class, then drill down a TreeView similar to the outline view Eclipse has for a current open file and at some point I click a button below and it generates the desired XML formatted text I would have typed manually, this is generated based on whatever in the tree I have highlighted.
I've designed and begun work on the front and back end, but the piece that keeps eluding me is harnessing Eclipse's content assist to gather a list of practically anything I could possibly call in a given project.
Can this be done? I've been combing Eclipse's documentation for a few days and fighting with the source download dying halfway repeatedly.
I am not 100% if that's it but I had an eclipse plugin with spider in it's name in mind, which does what you described.
Maybe it is this one: http://eclipse-plugins.2y.net/eclipse/plugin_details.jsp?id=202
Furthermore when writing Eclipse plugins, it is useful to press ctrl+shift+f1 (eclipse plugin spy) once having worked in the pde this should be possible.
It shows you info about all possible extensionpoints refering to your current view.