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Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=

..., and will speed sorts up slightly. UPDATE: utf8mb4/utf8mb4_unicode_ci is now the preferred character set/collation method. utf8_general_ci is advised against, as the performance improvement is negligible. See https://stackoverflow.com/a/766996/1432614 ...
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Namespace and class with the same name?

... fix that by fully qualifying the name: class C { Foo.Foo foo; } This now gives the ambiguity error “Foo in Foo.Foo is ambiguous between Foo.Foo and Bar.Foo”. We still don’t know what the first Foo refers to, and until we can figure that out, we don’t even bother to try to figure out wh...
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How to check for valid email address? [duplicate]

...g it even a little tighter. Seems safe to limit TLD to alphanumeric right now (still haven't seen a TLD that has non-ASCII chars). Using this now: re.compile(r"[^@\s]+@[^@\s]+\.[a-zA-Z0-9]+$") – gaefan Aug 29 '15 at 15:39 ...
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Setting the default value of a DateTime Property to DateTime.Now inside the System.ComponentModel De

Does any one know how I can specify the Default value for a DateTime property using the System.ComponentModel DefaultValue Attribute? ...
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How to write a:hover in inline CSS?

... You could do it at some point in the past. But now (according to the latest revision of the same standard, which is Candidate Recommendation) you can't . share | impr...
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Get all unique values in a JavaScript array (remove duplicates)

...et to store unique values. To get an array with unique values you could do now this: var myArray = ['a', 1, 'a', 2, '1']; let unique = [...new Set(myArray)]; console.log(unique); // unique is ['a', 1, 2, '1'] The constructor of Set takes an iterable object, like Array, and the spread ope...
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Equation (expression) parser with precedence?

...l, you actually have a hope at scaling up later, showing other people you know that parsers are the domain of parsing tools. Update: People here have offered much sound advice. My only warning against skipping the parsing tools or just using the Shunting Yard algorithm or a hand rolled recursive...
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In Python, how do I determine if an object is iterable?

...iterable object and with them the above code doesn't work well. As a real life example we can use Faker. The above code reports it being iterable but actually trying to iterate it causes an AttributeError (tested with Faker 4.0.2): >>> from faker import Faker >>> fake = Faker() &g...
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Removing trailing newline character from fgets() input

... Perhaps the simplest solution uses one of my favorite little-known functions, strcspn(): buffer[strcspn(buffer, "\n")] = 0; If you want it to also handle '\r' (say, if the stream is binary): buffer[strcspn(buffer, "\r\n")] = 0; // works for LF, CR, CRLF, LFCR, ... The function cou...
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bool to int conversion

... zero and the value true is converted to one. As for C, as far as I know there is no bool in C. (before 1999) So bool to int conversion is relevant in C++ only. In C, 4<5 evaluates to int value, in this case the value is 1, 4>5 would evaluate to 0. EDIT: Jens in the comment said, C99 ...