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UnboundLocalError on local variable when reassigned after first use
...es in functions differently depending on whether you assign values to them from inside or outside the function. If a variable is assigned within a function, it is treated by default as a local variable. Therefore, when you uncomment the line you are trying to reference the local variable c before ...
Enabling error display in PHP via htaccess only
...p_value error_reporting <integer>
Combined with the integer values from this page: http://php.net/manual/en/errorfunc.constants.php
Note if you use -1 for your integer, it will show all errors, and be future proof when they add in new types of errors.
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Legality of COW std::string implementation in C++11
...) (and on every return of pointer, reference, or iterator) does not suffer from that problem. I.e. (invariant) a buffer is at any time unshared, or else shared with no external refs. I thought you had intended the comment about this example as an informal bug report-as-a-comment, very sorry for misu...
Remove property for all objects in array
I want to remove the bad property from every object in the array. Is there a better way to do it than using a for loop and deleting it from every object?
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Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
...maphore - no recursion or inheritance, acts as a coherent resource counter from any desired initial count, threads only block where net count against the resource is zero.
Again, this varies somewhat by platform - especially what they call these things, but this should be representative of the con...
Rounding float in Ruby
...s a number, not a string. There is no way that the number 2.3 is different from 2.30, so there is no way to have an option to preserve trailing zeros. You could make your own class of numbers_with_significance but then we already have strings.
– Roobie Nuby
Apr...
How to solve error message: “Failed to map the path '/'.”
...rify further, I ended up changing the app pool identity for my web service from "ApplicationPoolIdentity" to "Network Service".
– Mary Hamlin
Sep 1 '12 at 23:34
65
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Changing the maximum length of a varchar column?
I'm trying to update the length of a varchar column from 255 characters to 500 without losing the contents. I've dropped and re-created tables before but I've never been exposed to the alter statement which is what I believe I need to use to do this. I found the documentation here: ALTER TABLE (Tra...
MySQL: multiple tables or one table with many columns?
...e a relatively small length limit (~8000 bytes). In my problem table (data from very lengthy insurance forms, more than 100 columns) we have multiple varchar columns, all UTF8. So we easily filled the ~8000 bytes limit and got "error 139 from storage engine" all the time. So we had to split the tabl...
Lambda function in list comprehensions
...ion.
I don't think the purpose of the OP was to generate a list of squares from 0 to 9. If that was the case, we could give even more solutions:
squares = []
for x in range(10): squares.append(x*x)
this is the good ol' way of imperative syntax.
But it's not the point. The point is W(hy)TF is this...