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How to set Python's default version to 3.x on OS X?
...on='python3'
in your ~/.profile, and then source ~/.profile in your ~/.bash_profile and/or your~/.zsh_profile with a line like:
[ -e ~/.profile ] && . ~/.profile
This way, your alias will work across shells.
With this, python command now invokes python3. If you want to invoke the "origi...
Is explicitly closing files important?
...of course for this magic to work the object must have the especial methods __enter__ and __exit__, in the latter the object do the close and any other cleanup stuff that need to be done at the end of the with statement...
– Copperfield
Mar 26 '16 at 13:02
...
How can I quickly sum all numbers in a file?
...ing as the awk solution in Ayman Hourieh's answer:
% perl -nle '$sum += $_ } END { print $sum'
If you're curious what Perl one-liners do, you can deparse them:
% perl -MO=Deparse -nle '$sum += $_ } END { print $sum'
The result is a more verbose version of the program, in a form that no one ...
What is the difference between String.Empty and “” (empty string)?
...private hidebysig instance string foo() cil managed
{
.maxstack 8
L_0000: ldstr "foo"
L_0005: ret
}
.method private hidebysig instance string bar() cil managed
{
.maxstack 8
L_0000: ldstr "bar"
L_0005: ldsfld string [mscorlib]System.String::Empty
L_000a: call string [msc...
iOS 7 parallax effect in my view controller
...omIOS7MotionEffectExtent = 10.0;
- (void)applyMotionEffects:(UIView *YOUR_VIEW) {
if (NSClassFromString(@"UIInterpolatingMotionEffect")) {
UIInterpolatingMotionEffect *horizontalEffect = [[UIInterpolatingMotionEffect alloc] initWithKeyPath:@"center.x"
...
libxml/tree.h no such file or directory
...ude/libxml2" to the Header Search Path (XCode 4.2), than it says that " "_OBJC_METACLASS_$_UIResponder", referenced from: _OBJC_METACLASS_$_D2GAppDelegate in MyDemoAppDelegate.o ld: symbol(s) not found for architecture i386". What can i do?
– NicTesla
A...
How to inherit from a class in javascript?
...sole issue?)
// In the Chrome console you should be able to drill down the __proto__ chain
// You can also look down the proto chain with Object.getPrototypeOf
// (Equivalent to tiger.__proto__)
console.log( Object.getPrototypeOf(tiger) ); // Mammal
console.log( Object.getPrototypeOf(Object.getPro...
Binding a WPF ComboBox to a custom list
...0">
<Grid>
<StackPanel>
<Button Click="Button_Click">asdf</Button>
<ComboBox ItemsSource="{Binding Path=PhonebookEntries}"
DisplayMemberPath="Name"
SelectedValuePath="Name"
SelectedValue="{Binding...
What does “program to interfaces, not implementations” mean?
...wered Apr 23 '10 at 10:31
this. __curious_geekthis. __curious_geek
40.1k2020 gold badges105105 silver badges132132 bronze badges
...
How to check if two arrays are equal with JavaScript? [duplicate]
...,3],[4,5,6]]) --> [[1,4],[2,5],[3,6]]
return arrays[0].map(function(_,i){
return arrays.map(function(array){return array[i]})
});
}
// helper functions
function allCompareEqual(array) {
// e.g. allCompareEqual([2,2,2,2]) --> true
// does not work with nested arra...