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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 do I run a Python program in the Command Prompt in Windows 7?
I'm trying to figure out how to run Python programs with the Command Prompt on Windows 7. (I should have figured this out by now...)
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How to use php serialize() and unserialize()
... means to put the structure into a "lower common denominator" that can be handled by things other than PHP, like databases, text files, sockets. The standard PHP function serialize is just a format to express such a thing, it serializes a data structure into a string representation that's unique to ...
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(...
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; ...
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.
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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...
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...
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(...
