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When should I use nil and NULL in Objective-C?
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technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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How to set child process' environment variable in Makefile
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I have GNU make 3.81, and all: <\n\t>export PROJ_ROOT=$(CURDIR)<\n\t>echo $(PROJ_ROOT)<\n> outputs the correct expansion for the first row, but only echo for the second one. PROJ_ROOT is not set after running make. Spaces around = gi...
How do I analyze a program's core dump file with GDB when it has command-line parameters?
...xt_ptr = "string in text segment";
(void)argv;
mmap_ptr = (char *)malloc(sizeof(data_ptr) + 1);
strcpy(mmap_ptr, data_ptr);
mmap_ptr[10] = 'm';
mmap_ptr[11] = 'm';
mmap_ptr[12] = 'a';
mmap_ptr[13] = 'p';
printf("text addr: %p\n", text_ptr);
printf("data addr: %p\n...
How do I use a Boolean in Python?
Does Python actually contain a Boolean value? I know that you can do:
7 Answers
7
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Why can't I use a list as a dict key in python?
..., with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. Lists are generally treated as if their value was derived from their content's values, for instance when checking (in-)equality. Many would - underst...
How do I include a pipe | in my linux find -exec command?
...ld result in only a single agrep process being spawned which would process all the output produced by numerous invocations of zcat.
If you for some reason would like to invoke agrep multiple times, you can do:
find . -name 'file_*' -follow -type f \
-printf "zcat %p | agrep -dEOE 'grep'\n" | s...
Casting vs using the 'as' keyword in the CLR
...d within the if body.) That's slightly annoying in some cases, so if you really care about introducing the smallest number of variables possible in every scope, you might still want to use is followed by a cast.
I don't think any of the answers so far (at the time of starting this answer!) have r...
How to wait for several Futures?
...ave several futures and need to wait until either any of them fails or all of them succeed.
8 Answers
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Can you find all classes in a package using reflection?
Is it possible to find all classes or interfaces in a given package? (Quickly looking at e.g. Package , it would seem like no.)
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Replace multiple characters in one replace call
... just have to chain. However, you could add a prototype:
String.prototype.allReplace = function(obj) {
var retStr = this;
for (var x in obj) {
retStr = retStr.replace(new RegExp(x, 'g'), obj[x]);
}
return retStr;
};
console.log('aabbaabbcc'.allReplace({'a': 'h', 'b': 'o'}))...