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How to return an empty ActiveRecord relation?
If I have a scope with a lambda and it takes an argument, depending on the value of the argument, I might know that there will not be any matches, but I still want to return a relation, not an empty array:
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How to auto-remove trailing whitespace in Eclipse?
...e. At least I couldn't find a setting for this in Formatter configuration, and it worked out of the box for built-in Java Conventions, Eclipse, Eclipse 2.1 styles, as well as GoogleStyle.
When using this set-up, you obviously need to also turn off the solution to part 1 of the question.
Eclipse ve...
how to change an element type using jquery
... answered Dec 21 '11 at 1:52
Andrew WhitakerAndrew Whitaker
116k2727 gold badges268268 silver badges292292 bronze badges
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Print function log /stack trace for entire program using firebug
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Firefox provides console.trace() which is very handy to print the call stack. It is also available in Chrome and IE 11.
Alternatively try something like this:
function print_call_stack() {
var stack = new Error().stack;
console.log("PRINTING CALL STACK");
console....
Python logging not outputting anything
...han info.
To change the level, just set it in the root logger:
'root':{'handlers':('console', 'file'), 'level':'DEBUG'}
In other words, it's not enough to define a handler with level=DEBUG, the actual logging level must also be DEBUG in order to get it to output anything.
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An async/await example that causes a deadlock
...nAsync awaits the Task returned by GetStringAsync. The context is captured and will be used to continue running the GetJsonAsync method later. GetJsonAsync returns an uncompleted Task, indicating that the GetJsonAsync method is not complete.
The top-level method synchronously blocks on the Task re...
How to check a radio button with jQuery?
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@Installero actually, prep is correct since 1.6, and required since 1.9.
– John Dvorak
Apr 29 '13 at 7:25
44
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What version of javac built my jar?
... version of the Java compiler was used to build a jar? I have a jar file, and it could have been built in any one of three JDKs. We need to know exactly which one, so we can certify compatibility. Is the compiler version embedded somewhere in the class files or jar?
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Android Studio - Where can I see callstack while debugging an android app?
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At the bottom panel you should have "5: Debug". Click on it and select "Debugger -> Threads"
You may need to find the "Threads" icon on the far right, or even click the "Restore Layout" button on the left to restore this window.
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What is non-blocking or asynchronous I/O in Node.js?
...rage is a blocking operation as it stalls execution to read. On the other hand, fetch is a non-blocking operation as it does not stall alert(3) from execution.
// Blocking: 1,... 2
alert(1);
var value = localStorage.getItem('foo');
alert(2);
// Non-blocking: 1, 3,... 2
alert(1);
fetch('example.com...