while True means loop forever. The while statement takes an expression and executes the loop body while the expression evaluates to (boolean) “true”. True always evaluates to boolean “true” and thus executes the loop body indefinitely. It’s an idiom that you’ll just get used to eventually! Most languages you’re likely to encounter have equivalent idioms. … Read more
Yes, this is expected. [C++11: 2.14.2/1]: An integer literal is a sequence of digits that has no period or exponent part. An integer literal may have a prefix that specifies its base and a suffix that specifies its type. The lexically first digit of the sequence of digits is the most significant. A decimal integer … Read more
Bitfields, carried over from C. Name is 40 bits wide, Colour is 24 bits wide. Your struct therefore has at least 64 bits. On my system 64 bits would be 8 bytes.
They always give the same result. In fact, not ‘ham’ in ‘spam and eggs’ appears to be special cased to perform a single “not in” operation, rather than an “in” operation and then negating the result: >>> import dis >>> def notin(): ‘ham’ not in ‘spam and eggs’ >>> dis.dis(notin) 2 0 LOAD_CONST 1 (‘ham’) … Read more
See the section on Substring removal in the Advanced Bash-Scripting Guide‡: ${string#substring} Deletes shortest match of substring from front of $string. ${string##substring} Deletes longest match of substring from front of $string. The substring may include a wildcard *, matching everything. The expression ${0##/*} prints the value of $0 unless it starts with a forward slash, … Read more
There is a shortcut for SELECT * FROM in standard SQL, so you can use it in psql: TABLE tablename; This syntax shorthand can only be used with a limited range of clauses. The manual: It can be used as a top-level command or as a space-saving syntax variant in parts of complex queries. Only … Read more
The src attribute should contain a valid URL. Since space characters are not allowed in URLs, you have to encode them. You can write: <img src=”https://stackoverflow.com/questions/4172579/buttons/bu%20hover.png” /> But not: <img src=”https://stackoverflow.com/questions/4172579/buttons/bu+hover.png” /> Because, as DavidRR rightfully points out in his comment, encoding space characters as + is only valid in the query string portion of … Read more
Do not use dot for behavior. Use dot to access or set attribute like stuff, typically attributes declared as properties. x = foo.name; // good foo.age = 42; // good y = x.retain; // bad k.release; // compiler should warn, but some don’t. Oops. v.lockFocusIfCanDraw; /// ooh… no. bad bad bad For folks new to … Read more
It’s the lambda operator. From C# 3 to C# 5, this was only used for lambda expressions. These are basically a shorter form of the anonymous methods introduced in C# 2, but can also be converted into expression trees. As an example: Func<Person, string> nameProjection = p => p.Name; is equivalent to: Func<Person, string> nameProjection … Read more
Use the ll (el-el) long-long modifier with the u (unsigned) conversion. (Works in windows, GNU). printf(“%llu”, 285212672);