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What does 'wb' mean in this code, using Python?
...nd binary
files; the end-of-line characters in
text files are automatically altered
slightly when data is read or written.
This behind-the-scenes modification to
file data is fine for ASCII text
files, but it’ll corrupt binary data
like that in JPEG or EXE files.
...
Can you use an alias in the WHERE clause in mysql?
....
WHERE (sum(reviews.rev_rating)/count(reviews.rev_id))>5
BUT! Not all expressions will be allowed - using an aggregating function like SUM will not work, in which case you'll need to use a HAVING clause.
From the MySQL Manual:
It is not allowable to refer to a
column alias in a WHERE...
Protected methods in Objective-C
...rClassProtectedMethods <NSObject>
- (void) protectMethod:(NSObject *)foo;
@end
@interface SuperClass (ProtectedMethods) < SuperClassProtectedMethods >
@end
SuperClass.m: (compiler will now force you to add protected methods)
#import "SuperClassProtectedMethods.h"
@implementation Supe...
Logical Operators, || or OR?
...
and $e = true || $x = 'foo' will not define $x because of short-circuiting, not because of higher precedence.
– Matt Kieran
Jul 31 '14 at 1:18
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Breaking out of nested loops [duplicate]
... return statement can be used to exit the outermost loop at any time.
def foo():
for x in range(10):
for y in range(10):
print(x*y)
if x*y > 50:
return
foo()
If it's hard to extract that function you could use an inner function, as @bjd2385 s...
How to check whether a string contains a substring in Ruby
...returns the index of the character where the match happens. For example:
"foobar" =~ /bar/ # returns 3
"foobar" =~ /foo/ # returns 0
"foobar" =~ /zzz/ # returns nil
It's important to note that in Ruby only nil and the boolean expression false evaluate to false. Everything else, including an em...
Valid to use (anchor tag) without href attribute?
.... Originally the HTML specification allowed for named anchors (<a name="foo">) and linked anchors (<a href="#foo">).
The named anchor format is less commonly used, as the fragment identifier is now used to specify an [id] attribute (although for backwards compatibility you can still spe...
How to get the unix timestamp in C#
...cNow.ToUnixTimeSeconds()
To get the timestamp from a DateTime:
DateTime foo = DateTime.UtcNow;
long unixTime = ((DateTimeOffset)foo).ToUnixTimeSeconds();
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Ruby / Rails - Change the timezone of a Time, without changing the value
I have a record foo in the database which has :start_time and :timezone attributes.
11 Answers
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How to get relative path from absolute path
...ow an exception if the file or path doesn't exist since this could be a totally legal case.
– VVS
Jun 2 '09 at 12:01
2
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