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Can I assume (bool)true == (int)1 for any C++ compiler?
...are redundant. In your expression:
true == 1
Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.
Reference: 4.7 [conv.integral] / 4: If the source type is bool... true is converted to one.
...
How can I know which parts in the code are never used?
..., it's much more difficult. Statically it requires whole program analysis, and even though link time optimization may actually remove dead code, in practice the program has been so much transformed at the time it is performed that it is near impossible to convey meaningful information to the user.
...
How to place two divs next to each other?
...pper div to contain both the floated children, or it will think it's empty and not put the border around them
Floating both divs:
#wrapper {
width: 500px;
border: 1px solid black;
overflow: hidden; /* add this to contain floated children */
}
#first {
width: 300px;
float:left; ...
Is < faster than
...n two machine instructions:
A test or cmp instruction, which sets EFLAGS
And a Jcc (jump) instruction, depending on the comparison type (and code layout):
jne - Jump if not equal --> ZF = 0
jz - Jump if zero (equal) --> ZF = 1
jg - Jump if greater --> ZF = 0 and SF = OF
(etc...)
Exa...
Extracting numbers from vectors of strings
...
How about
# pattern is by finding a set of numbers in the start and capturing them
as.numeric(gsub("([0-9]+).*$", "\\1", years))
or
# pattern is to just remove _years_old
as.numeric(gsub(" years old", "", years))
or
# split by space, get the element in first index
as.numeric(sapply(...
Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
...
Short of closing and reopening your tty (i.e. logging off and back on, which may also terminate some of your background processes in the process) you only have one choice left:
attach to the process in question using gdb, and run:
p dup2(...
jQuery - add additional parameters on submit (NOT ajax)
...answer, but added the NAME attribute to let it show in the form collection and changed VALUE to VAL
Also checked the ID of the FORM (form1 in my case)
used the Firefox firebug to check whether the element was inserted.
Hidden elements do get posted back in the form collection, only read-only field...
Initialize a byte array to a certain value, other than the default null? [duplicate]
... { 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20 };
For larger arrays use a standard for loop. This is the most readable and efficient way to do it:
var sevenThousandItems = new byte[7000];
for (int i = 0; i < sevenThousandItems.Length; i++)
{
sevenThousandItems[i] = 0x20;
}
Of course, if you...
How do C++ class members get initialized if I don't do it explicitly?
...ve a class with private memebers ptr , name , pname , rname , crname and age . What happens if I don't initialize them myself? Here is an example:
...