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How do I install an old version of Django on virtualenv?
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There was never a Django 1.0.7. The 1.0 series only went up to 1.0.4. You can see all the releases in the tags section of the Django code repository.
However to answer your question, don't use easy_install, use pip. (If it's not already installed, do ...
Iterating Through a Dictionary in Swift
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360
Dictionaries in Swift (and other languages) are not ordered. When you iterate through the dictio...
Equivalent of varchar(max) in MySQL?
...the table.
mysql> CREATE TABLE foo ( v VARCHAR(65534) );
ERROR 1118 (42000): Row size too large. The maximum row size for the used table type, not counting BLOBs, is 65535. This includes storage overhead, check the manual. You have to change some columns to TEXT or BLOBs
But if we try decreasi...
How can you sort an array without mutating the original array?
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Putzi SanPutzi San
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How do I check for null values in JavaScript?
... will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks against -1)) for funct...
Concatenating string and integer in python
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answered Jul 19 '12 at 10:43
user647772user647772
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Deleting lines from one file which are in another file
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answered Jan 24 '11 at 9:06
gabuzogabuzo
6,27833 gold badges2323 silver badges3535 bronze badges
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PHP regular expressions: No ending delimiter '^' found in
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PHP regex strings need delimiters. Try:
$numpattern="/^([0-9]+)$/";
Also, note that you have a lower case o, not a zero. In addition, if you're just validating, you don't need the capturing group, and can simplify the regex to /^\d+$/.
Example: http://ideone.com/Ec3zh
See also:...
How to count items in a Go map?
...ed from the now-retired SO documentation:
m := map[string]int{}
len(m) // 0
m["foo"] = 1
len(m) // 1
If a variable points to a nil map, then len returns 0.
var m map[string]int
len(m) // 0
Excerpted from Maps - Counting map elements. The original author was Simone Carletti. Attribution det...
Which, if any, C++ compilers do tail-recursion optimization?
...s such as:
int bar(int, int);
int foo(int n, int acc) {
return (n == 0) ? acc : bar(n - 1, acc + 2);
}
int bar(int n, int acc) {
return (n == 0) ? acc : foo(n - 1, acc + 1);
}
Letting the compiler do the optimisation is straightforward: Just switch on optimisation for speed:
For MSVC,...