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How to step back in Eclipse debugger?
...The current project I'm working on requires a minimum of 5 seconds to read and initialize data from a file before anything can be done. If I overstep in the debugger, I have to terminate the program and restart, and this takes a fair bit of time.
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Why does pattern matching in Scala not work with variables?
...sense that the default behaviour is for lowercase patterns to be variables and not stable identifiers. Only when you see something beginning with upper case, or in back ticks, do you need to be aware that it comes from the surrounding scope.
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What are some common uses for Python decorators? [closed]
...ple! No idea what it does though. An explanation what you are doing there, and how the decorator solves the problem would be very nice.
– MeLight
Jun 15 '14 at 16:00
8
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When does System.gc() do something?
... on lots of factors, like which JVM you're running on, which mode it's in, and which garbage collection algorithm it's using.
I wouldn't depend on it in your code. If the JVM is about to throw an OutOfMemoryError, calling System.gc() won't stop it, because the garbage collector will attempt to f...
SQL to determine minimum sequential days of access?
...n user has accessed a website (in a 24 hour UTC period). It has many thousands of records, but only one record per day per user. If the user has not accessed the website for that day, no record will be generated.
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Listening for variable changes in JavaScript
... is an old thread but now this effect is possible using accessors (getters and setters): https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects#Defining_getters_and_setters
You can define an object like this, in which aInternal represents the field a:
x = {
aInternal:...
How do I output coloured text to a Linux terminal?
..., ASCII 27. It is followed by [, then zero or more numbers separated by ;, and finally the letter m. The numbers describe the colour and format to switch to from that point onwards.
The codes for foreground and background colours are:
foreground background
black 30 40
red ...
Eclipse “Invalid Project Description” when creating new project from existing source
... that project from the source code before, but then I deleted that project and deleted its whole directory, before adding the source code directory again. I tried everything like cleaning and restarting, but nothing worked. I looked in my workspace directory, but there are no traces for the old proj...
Switch statement multiple cases in JavaScript
...one feature of switch ... case. It's too easy to forget a break statement, and if you use fall through intentionally, those forgotten break statements can be very hard to spot. This method lookup version also has lots of great features that switch ... case lacks, such as dynamic extensibility, or t...
django syncdb and an updated model
...support for migrations - take a look at the documentation.
For Django 1.6 and earlier
Django doesn't support migrations out of the box. There is a pluggable app for Django that does exactly that though, and it works great. It's called South.
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