Reading some questions here on SO about conversion operators and constructors got me thinking about the interaction between them, namely when there is an 'ambiguous' call. Consider the following code: class A; class B { public: B(){} B(const A&) //conversion constructor { cout << "cal...
For example, instead of - op =; val it = fn : ''a * ''a -> bool I would rather have - op =; val it = fn : ''a -> ''a -> bool for use in val x = getX() val l = getList() val l' = if List.exists ((op =) x) l then l else x::l Obviously I can do this on my own, for example, val l' = if List.exists (fn y => x = y) l then l else x::l...
It's hard to search this in google because it consists of symbol? What does ||= stand for? And how does it work? Thanks. ...
I'm well aware that in C++ int someValue = i++; array[i++] = otherValue; has different effect compared to int someValue = ++i; array[++i] = otherValue; but every once in a while I see statements with prefix increment in for-loops or just by their own: for( int i = 0; i < count; ++i ) { //do stuff } or for( int i = 0; i < ...
Why is sizeof considered an operator and not a function? What property is necessary for something to qualify as operator? ...
I can't search for | in Google. If you had found it in a software source code that you are trying to interpret, you didn't know what it does and you couldn't ask other people for help, how would you find out what it does? ...
I've just walked into this code: val.enabled = !!enable and have no idea what does "!!" do... I googled JavaScript operators but haven't found this one. ...
I'm trying to get the list of defined operators for a specific type in order to see what kind of operations can be applied to that type. For example, the type Guid supports operations == and !=. So if user wants to apply <= operation for a Guid type i can handle this situation before an exception occurs. Or if i could have the list ...
What is the meaning of this expression " () =>". I have seen it used in a constructor: return new MyItem(itemId, () => MyFunction(myParam)); Thank you ...
bool operator()(Iterator it1, Iterator it2) const { return (*it1 < *it2); } Can someone explain this function for me, thanks! is this means overload the operator ()? after overload this, how to use it ? ...
How do I bitwise shift right/left in VB.NET? Does it even have operators for this, or do I have to use some utility method? ...
According to this, !==! is the not-equal string operator. Trying it, I get: C:\> if "asdf" !==! "fdas" echo asdf !==! was unexpected at this time. What am I doing wrong? ...
What is the difference between && and and operators in Ruby? ...
Unfortunately, search engines have failed me using this query. For instance: int foo = ~bar; ...
I wonder why ruby give and, or less precedence than &&, || , and assign operator? Is there any reason? ...
What is the difference between these two operators? Specifically, what difference in $a will lead to different behavior between the two? $a =~ /^pattern$/ $a eq 'pattern' ...
I have two RadioButtons: r1 and r2. I have to enable both on Enabled = true and disable only unchecked on Enabled = false public bool Enabled { set { if(value) { r1.Enabled = value; // true r2.Enabled = value; } else { if(!r1.Checked) { r1.Enabled = value; // false if not checked ...
class FormatFloat(FormatFormatStr): def __init__(self, precision=4, scale=1.): FormatFormatStr.__init__(self, '%%1.%df'%precision) self.precision = precision self.scale = scale def toval(self, x): if x is not None: x = x * self.scale return x def fromstr(self, s): ...
In source code I found this line: if ((modifiers & ~KeyEvent.SHIFT_MASK) != 0) .... Does somebody know what the ~ means? Thanks ...
I am a newbie to Python. I notice that a pre-increment/decrement operator can be applied on a variable (like ++count). It compiles, but it does not actually change the value of the variable! What is the behavior of the pre-increment/decrement operators (++/--) in Python? Why does Python deviate from the behavior of these operators seen ...