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Detecting an undefined object property
...ined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an identifier is the special va...
Cannot create or edit Android Virtual Devices (AVD) from Eclipse, ADT 22.6
...T 22.6.0 ONLY, THESE BUGS SUBSEQUENTLY FIXED IN FOLLOWING BUILDS
Download and install new ADT v22.6.1 from here (zip) or use SDK manager to update
Seems like some bug from Google side, this problem found after "ADT 22.6" update. Widely reported on "Android Open Source Project - Issue Tracker" and ...
Why would one omit the close tag?
...of the file. The header problem seems irrelevant in the following context (and this is the only good argument so far):
14 ...
Vim and Ctags tips and tricks [closed]
...alled Ctags (to help with C++ development) with my Vim (or rather gVim), and would like to find out your favorite commands, macros, shortcuts, tips that go along with it...
...
Why hasn't functional programming taken over yet?
...programs; No side effects
Real-world programs are all about side effects and mutation. When the user presses a button it's because they want something to happen. When they type in something, they want that state to replace whatever state used to be there. When Jane Smith in accounting gets married...
What is declarative programming? [closed]
...n you write your code in such a way that it describes what you want to do, and not how you want to do it. It is left up to the compiler to figure out the how.
Examples of declarative programming languages are SQL and Prolog.
...
Difference between app.all('*') and app.use('/')
Is there a useful difference between app.all('*', ... ) and app.use('/', ...) in Node.JS Express?
7 Answers
...
How to check if DST (Daylight Saving Time) is in effect, and if so, the offset?
...code uses the fact that getTimezoneOffset returns a greater value during Standard Time versus Daylight Saving Time (DST). Thus it determines the expected output during Standard Time, and it compares whether the output of the given date the same (Standard) or less (DST).
Note that getTimezoneOffset...
For-each over an array in JavaScript
...-of loop (ES2015+ only),
Array#forEach (spec | MDN) (or its relatives some and such) (ES5+ only),
a simple old-fashioned for loop,
or for-in with safeguards.
But there's lots more to explore, read on...
JavaScript has powerful semantics for looping through arrays and array-like objects. I've s...
SQL left join vs multiple tables on FROM line?
...
The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER joins in ...