There are multiple ways of doing this. The first one uses destructuring only and assigns the properties of options to properties on this: class Foo { constructor(options) { ({one: this.one, two: this.two} = options); // Do something else with the other options here } } The extra parentheses are needed, otherwise the JS engine might … Read more
Yes and yes is the answer. This is also true of structs in C. typedef struct { int a[100]; } S; S s1; s1.a[0] = 42; S s2; s2 = s1; // array copied
Remember that assignment is done right to left, and that they are normal expressions. So from the compilers perspective the line sample1 = sample2 = 0; is the same as sample1 = (sample2 = 0); which is the same as sample2 = 0; sample1 = sample2; That is, sample2 is assigned zero, then sample1 is … Read more
In PL/pgSQL you can SELECT INTO as many variables at once as you like directly. You just had the syntax backwards: SELECT INTO unsolvedNodes, lengths array_agg(DISTINCT idDestination), array_agg(length) FROM road WHERE idOrigin = ANY(solvedNodes) AND NOT (idDestination = ANY(solvedNodes)); You have the keyword INTO followed by a list of target variables, and you have a … Read more
All the expressions to the right of the assignment operator are evaluated before any of the assignments are made. From the Python tutorial: First steps towards programming: The first line contains a multiple assignment: the variables a and b simultaneously get the new values 0 and 1. On the last line this is used again, … Read more
You probably confused by the difference between null and undefined, For example: const { dogName=”snickers” } = { dogName: undefined } console.log(dogName) // what will it be? ‘snickers’! const { dogName=”snickers” } = { dogName: null } console.log(dogName) // what will it be? null! const { dogName=”snickers” } = { dogName: false } console.log(dogName) // … Read more
When you say let 5 = 10 it’s not a redefinition of 5, it’s a pattern matching, the same which occurs when you say foo 5 = undefined … foo 10 … The pattern simply fails if it’s ever matched. In let-expressions the match is lazy. This means the match is only being done when … Read more
Just use an empty byte string, b”. However, concatenating to a string repeatedly involves copying the string many times. A bytearray, which is mutable, will likely be faster: msg = bytearray() # New empty byte array # Append data to the array msg.extend(b”blah”) msg.extend(b”foo”) To decode the byte array to a string, use msg.decode(encoding=’utf-8′).
lvalue means “left value” — it should be assignable. You cannot change the value of text since it is an array, not a pointer. Either declare it as char pointer (in this case it’s better to declare it as const char*): const char *text; if(number == 2) text = “awesome”; else text = “you fail”; … Read more
Ruby interpreter initializes a local variable with nil when it sees an assignment to it. It initializes the local variable before it executes the assignment expression or even when the assignment is not reachable (as in the example below). This means your code initializes a with nil and then the expression a = nil will … Read more