Title says it all. What does the pound symbol do when you use it in LUA scripting?
✓ ANSWER ACCEPTED
What does # do?
2 answers
✓ Accepted answer
The number operator (#) returns the number of elements in a list (aka. table).
list = {"hello", 1, true};
print(#list);
--> 3
The # unary operator refers to table length (the number of things in a table being used as a list). Using it looks like this:
#list
(It is a unary operator, so syntactically it acts the same way that unary minus (negation) does, e.g., just like -x)
It counts the number of indices in a table starting at 1 until it finds a nil.
E.g., these are the lengths of the following tables:
print( #{1,3,5,-5,7} );
-- 5
print(
#{
[1] = 5,
[2]=4,
[4]=9
}
);
-- 2, since index 3 is nil
print(
#{
1,
5,
cat=three,
false,
[4] = true,
[0] = 2,
[6] = 99
}
);
-- 4; Counting indices 1, 2, [3] is false; [4] is true.
-- 'cat' and '0' are not indices counted by table length;
-- [6] is not counted since there is no 5
print(
#{
1,
nil,
2,
nil,
3
}
);
-- Length is 1, since value at [2] is `nil`.
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2 comments
Your answer was simpler and easier to understand.
Taslem's answer was more informative though which is more beneficial than a simple answer.