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Creating functions in a loop
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You're running into a problem with late binding -- each function looks up i as late as possible (thus, when called after the end of the loop, i will be set to 2).
Easily fixed by forcing early binding: change def f(): to def f(i=i): like...
How to move columns in a MySQL table?
... work, for example, in PostgreSQL or many other DBMSs.
Another edit: As pointed out by @Luis Rossi in a comment, you need to completely specify the altered column definition just before the AFTER modifier. The above examples just have VARCHAR(50), but if you need other characteristics (such as NOT ...
Controlling the screenshot in the iOS 7 multitasking switcher
...OS 7 and especially the screenshot that the OS takes when the app is going into hibernation.
8 Answers
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What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how
...and "maven.compiler.target" properties must have some Eclipse Maven plugin interaction as the problem just vanished.
– JasonTolotta
Mar 19 '19 at 1:55
add a comment
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Using ping in c#
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There's no point in wrapping the Ping instance with a using if try/catch/finally is employed properly. It's one or the other not both. See stackoverflow.com/questions/278902/….
– JamieSee
Feb 1 '19...
Difference between matches() and find() in Java Regex
...compile("\\d\\d\\d");
Matcher m = p.matcher("a123b");
System.out.println(m.find());
System.out.println(m.matches());
p = Pattern.compile("^\\d\\d\\d$");
m = p.matcher("123");
System.out.println(m.find());
System.out.println(m.matches());
}
/* output:
true
false
true
tru...
postgresql COUNT(DISTINCT …) very slow
...s significantly slower than count(x) then you can speed up this query by maintaining x value counts in different table, for example table_name_x_counts (x integer not null, x_count int not null), using triggers. But your write performance will suffer and if you update multiple x values in single tra...
onTouchListener warning: onTouch should call View#performClick when a click is detected
...ired to call performClick, right? In this case I don't understand why the lint warning is still there
– Jiechao Wang
Nov 13 '17 at 22:40
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What is an Intent in Android?
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An Intent is an "intention" to perform an action; in other words,
a messaging object you can use to request an action from another app component
An Intent is basically a message to say you did or want something to happen. ...
What platforms have something other than 8-bit char?
Every now and then, someone on SO points out that char (aka 'byte') isn't necessarily 8 bits .
12 Answers
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