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Best way to iterate through a Perl array
... #2 is good when you do queues (e.g. breadth-first searches): my @todo = $root; while (@todo) { my $node = shift; ...; push @todo, ...; ...; }
– ikegami
Feb 2 '15 at 14:40
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How come an array's address is equal to its value in C?
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That's because the array name (my_array) is different from a pointer to array. It is an alias to the address of an array, and its address is defined as the address of the array itself.
The pointer is a normal C variable on the stack, however. Thus, you ca...
Globally override key binding in Emacs
... for that key? I want to override all major/minor mode maps and make sure my binding is always in effect.
8 Answers
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How to assign the output of a command to a Makefile variable
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Use the Make shell builtin like in MY_VAR=$(shell echo whatever)
me@Zack:~$make
MY_VAR IS whatever
me@Zack:~$ cat Makefile
MY_VAR := $(shell echo whatever)
all:
@echo MY_VAR IS $(MY_VAR)
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Alternatives to gprof [closed]
... **. When that is understood, you can see that -
gprof embodies certain myths about performance, such as:
that program counter sampling is useful.
It is only useful if you have an unnecessary hotspot bottleneck such as a bubble sort of a big array of scalar values. As soon as you, for example, ...
Check if a given key already exists in a dictionary and increment it
...ct (available for Python 2.5+). This
from collections import defaultdict
my_dict = defaultdict(int)
my_dict[key] += 1
will do what you want.
For regular Python dicts, if there is no value for a given key, you will not get None when accessing the dict -- a KeyError will be raised. So if you want...
How do I set up a basic Ruby project?
... you can use the bundle gem command and rspec --init.
~/code $ bundle gem my_lib
create my_lib/Gemfile
create my_lib/Rakefile
create my_lib/LICENSE.txt
create my_lib/README.md
create my_lib/.gitignore
create my_lib/my_lib.gemspec
create my_lib/lib/my...
ES6 class variable alternatives
... true class variable you'd want to do something like the following:
class MyClass {}
MyClass.foo = 'bar';
From within a class method that variable can be accessed as this.constructor.foo (or MyClass.foo).
These class properties would not usually be accessible from to the class instance. i.e. My...
File name? Path name? Base name? Naming standard for pieces of a path
I keep getting myself in knots when I am manipulating paths and file names, because I don't have a common naming system that I use.
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Why do I need to do `--set-upstream` all the time?
...g the syntax for git branch --set-upstream 1 is to do:
git push -u origin my_branch
... the first time that you push that branch. Or, to push to the current branch to a branch of the same name (handy for an alias):
git push -u origin HEAD
You only need to use -u once, and that sets up the asso...