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Simple explanation of MapReduce?
...rite it like this
A = [7, 8, 9]
sum = A.reduce( 0, (x, y) => x + y )
Now it's a little confusing why there are 2 arguments (0 and the function with x and y) passed. For a reduce function to be useful, it must be able to take 2 items, compute something and "reduce" that 2 items to just one sing...
Does the APNS device token ever change, once created?
...ferent devices with the exact same APNS token. I see in front of me right now an iPad 2, and an iPhone 3GS that have sent us the same token. Can anyone else confirm this behavior?
– DougW
Jun 23 '12 at 1:26
...
How to use a variable to specify column name in ggplot
...
From the release notes of ggplot2 V3.0.0 :
aes() now supports quasiquotation so that you can use !!, !!!, and
:=. This replaces aes_() and aes_string() which are now
soft-deprecated (but will remain around for a long time).
The idiomatic way now would be to convert ...
Setting default value for TypeScript object passed as argument
...
Actually, there appears to now be a simple way. The following code works in TypeScript 1.5:
function sayName({ first, last = 'Smith' }: {first: string; last?: string }): void {
const name = first + ' ' + last;
console.log(name);
}
sayName({ first...
How to get the name of enumeration value in Swift?
...
As of Xcode 7 beta 5 (Swift version 2) you can now print type names and enum cases by default using print(_:), or convert to String using String's init(_:) initializer or string interpolation syntax. So for your example:
enum City: Int {
case Melbourne = 1, Chelyabin...
How can I reliably determine the type of a variable that is declared using var at design time?
... a local can be expensive so we want to defer that work if we need to.
We now have a lazily-built database that can tell us the type of every local. So, getting back to that "foo." -- we figure out which statement the relevant expression is in and then run the semantic analyzer against just that st...
A valid provisioning profile for this executable was not found for debug mode
...r-->right click your iPhone -->Add device to provisioning portal
8) Now make sure you have selected the appropriate code signing identity in edit project settings -> build --> code signing
Build and run. Good luck!
...
The Role Manager feature has not been enabled
... After adding above to web.config roleManager is enabled. But now I am getting exception Unable to connect to SQL Server database
– Irfan Yusanif
Jan 4 '16 at 13:51
...
MySQL: Transactions vs Locking Tables
...posit all the service fees charged on the transaction. Given (as everyone knows these days) that banks are extraordinarily stupid, let's say their system works like this:
$balance = "GET BALANCE FROM your ACCOUNT";
if ($balance < $amount_being_paid) {
charge_huge_overdraft_fees();
}
$balance...
Why can't I save CSS changes in Firebug? [closed]
...S and SAVE on local file system using Chrome Developer Tools
I tried it now and it works great highlighting the changed lines. Just click Save and you're done! :)
Here's a video explaining this and much more: Google I/O 2011: Chrome Dev Tools Reloaded
I hope it helps if it doesn't matter to you...