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How to remove constraints from my MySQL table?
...column to other tables columns. Mine had a standard name given to it. Also now I now that you can drop foreign keys safetely without the column itself being dropped
– Lealo
Aug 18 '17 at 0:35
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Cast Int to enum in Java
...lain why you regard MyEnum.values()[x] as an expensive operation. I don't know how it works in details, but to me it seems like accessing an element in an Array would be no big deal, aka constant time. If the array has to be build it takes O(n) time, which is the same runnning time as your solution....
Declare and initialize a Dictionary in Typescript
... true;
}
toLookup(): IDictionary {
return this;
}
}
Now we declare the Person specific type and Dictionary/Dictionary interface. In the PersonDictionary note how we override values() and toLookup() to return the correct types.
interface IPerson {
firstName: string;
la...
What's the yield keyword in JavaScript?
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Late answering, probably everybody knows about yield now, but some better documentation has come along.
Adapting an example from "Javascript's Future: Generators" by James Long for the official Harmony standard:
function * foo(x) {
while (true) {
...
How can I open multiple files using “with open” in Python?
...asks. No duplicate writing or failing to write. So I am really curious to know why my answer is considered to be wrong, suboptimal or anything like that.
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What does the PHP error message “Notice: Use of undefined constant” mean?
...sage is due to the unfortunate fact that PHP will implicitly declare an unknown token as a constant string of the same name.
That is, it's trying to interpret this (note the missing quote marks):
$_POST[department]
The only valid way this would be valid syntax in PHP is if there was previously ...
How to pass arguments to a Button command in Tkinter?
...arameter assignment for the lambda"? I did not get lambda to work and thus now use partial.
– Klamer Schutte
Feb 18 '15 at 22:14
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show 13 m...
How to profile a bash shell script slow startup?
...2 2> >(tee /tmp/sample-time.$$.log |
sed -u 's/^.*$/now/' |
date -f - +%s.%N >/tmp/sample-time.$$.tim)
set -x
Doing this will run date only once. There is a quick demo/test to show how it work:
for i in {1..4};do echo now;sleep .05;done| date -f - +%N
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__lt__ instead of __cmp__
...ot self<other
def __le__(self, other):
return not other<self
Now your class can define just __lt__ and multiply inherit from ComparableMixin (after whatever other bases it needs, if any). A class decorator would be quite similar, just inserting similar functions as attributes of the ne...
Where to find Java JDK Source Code? [closed]
... just had to tell Eclipse where this file is and I could see the code. But now I don't have the file anymore...
11 Answers
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