ampersand

how does the ampersand(&) sign work in c++? [duplicate]

由 不打扰是莪最后的温柔 提交于 2019-11-26 19:47:09
Possible Duplicate: What are the differences between pointer variable and reference variable in C++? This is confusing me: class CDummy { public: int isitme (CDummy& param); }; int CDummy::isitme (CDummy& param) { if (&param == this) { return true; //ampersand sign on left side?? } else { return false; } } int main () { CDummy a; CDummy* b = &a; if ( b->isitme(a) ) { cout << "yes, &a is b"; } return 0; } In C & usually means the address of a var. What does it mean here? Is this a fancy way of pointer notation? The reason I am assuming it is a pointer notation because this is a pointer after

Ampersand (&) at the end, and part of, a selector in SASS

由 大城市里の小女人 提交于 2019-11-26 19:09:29
I have a problem I'm struggling with. I have this mixin (which is an attempt to port some less to sass ): @mixin button-variant($color, $background, $border) { ... .foreverAlone{ ... } .iThink .illNeverWork& { color: $pinkUnicornRainbow; ... } } Which obviously is not working :D I would like it to generate something like: .callerClass .foreverAlone{ ... } .callerClass .iThink .illNeverWork.callerClass{ color: #123ABC; ... } The mixin is called inside various div classes, so it is not possible to make it static (easily). Is there any workaround from some Sass pro (or not pro, but smarter than I

are characters # or & allowed in xml?

由 不想你离开。 提交于 2019-11-26 17:14:40
问题 i have values with special chars that encoded to ascii in my xml. for example : <?xml version="1.0" encoding="UTF-8"?> <response> <name>Žirmūnų</name> </response> but when i parse value name i get only & as value. Is it allowed to use # or & in xml? or i have to use cdata necessarily? 回答1: The & character appears to be illegal, use (below) instead. & Invalid Characters in XML The # character should be OK. Also this may be useful: http://xml.silmaril.ie/specials.html. 回答2: & needs to be

What does an ampersand (&) mean in the Swift language?

由 北慕城南 提交于 2019-11-26 13:00:55
问题 I know about the ampersand as a bit operation but sometimes I see it in front of variable names. What does putting an & in front of variables do? 回答1: It works as an inout to make the variable an in-out parameter. In-out means in fact passing value by reference, not by value. And it requires not only to accept value by reference, by also to pass it by reference, so pass it with & - foo(&myVar) instead of just foo(myVar) As you see you can use that in error handing in Swift where you have to

sas MACRO ampersand

由 若如初见. 提交于 2019-11-26 10:01:58
问题 %let test = one; %let one = two; %put &test; %put &&test; %put &&&test; %put &&&&test; %put &&&&&test; Well. I\'m TOTALLY BEATEN by these ampersands. I don\'t understand why they need SO MANY ampersands before a macro variable. Is there any trick to master the usage of ampersand? BTW, what are the five results, correspondingly? 回答1: With a single set of ampersands, what you get is pretty boring; after one, odd number of ampersands leads to resolving twice, even number of ampersands resolves

how does the ampersand(&) sign work in c++? [duplicate]

由 谁都会走 提交于 2019-11-26 07:25:22
问题 This question already has answers here : Closed 7 years ago . Possible Duplicate: What are the differences between pointer variable and reference variable in C++? This is confusing me: class CDummy { public: int isitme (CDummy& param); }; int CDummy::isitme (CDummy& param) { if (&param == this) { return true; //ampersand sign on left side?? } else { return false; } } int main () { CDummy a; CDummy* b = &a; if ( b->isitme(a) ) { cout << \"yes, &a is b\"; } return 0; } In C & usually means the

Why does scanf() need & operator (address-of) in some cases, and not others?

由 穿精又带淫゛_ 提交于 2019-11-26 06:46:26
问题 Why do we need to put a & operator in scanf() for storing values in an integer array but not while storing a string in a char array? int a[5]; for(i=0;i<5;i++) scanf(\"%d\",&a[i]); but char s[5]; scanf(\"%s\",s); We need to pass in the address of the place we store the value, since array is a pointer to first element. So in the case with int/float arrays it basically means (a+i) . But whats the case with strings? 回答1: scanf accepts a pointer to whatever you are putting the value in. In the

&#39;and&#39; (boolean) vs &#39;&&#39; (bitwise) - Why difference in behavior with lists vs numpy arrays?

由 我与影子孤独终老i 提交于 2019-11-26 03:15:43
问题 What explains the difference in behavior of boolean and bitwise operations on lists vs NumPy arrays? I\'m confused about the appropriate use of & vs and in Python, illustrated in the following examples. mylist1 = [True, True, True, False, True] mylist2 = [False, True, False, True, False] >>> len(mylist1) == len(mylist2) True # ---- Example 1 ---- >>> mylist1 and mylist2 [False, True, False, True, False] # I would have expected [False, True, False, False, False] # ---- Example 2 ---- >>>

How do I escape ampersands in XML so they are rendered as entities in HTML?

由 谁说胖子不能爱 提交于 2019-11-25 23:39:38
问题 I have some XML text that I wish to render in an HTML page. This text contains an ampersand, which I want to render in its entity representation: & . How do I escape this ampersand in the source XML? I tried & , but this is decoded as the actual ampersand character ( & ), which is invalid in HTML. So I want to escape it in such a way that it will be rendered as & in the web page that uses the XML output. 回答1: When your XML contains &amp; , this will result in the text & . When you use that in
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