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How can I check for “undefined” in JavaScript? [duplicate]
...n window; // true
"theFoo" in window; // false
If you are interested in knowing whether the variable hasn't been declared or has the value undefined, then use the typeof operator, which is guaranteed to return a string:
if (typeof myVar !== 'undefined')
Direct comparisons against undefined are ...
force client disconnect from server with socket.io and nodejs
...
Edit: This is now possible
You can now simply call socket.disconnect() on the server side.
My original answer:
This is not possible yet.
If you need it as well, vote/comment on this issue.
...
When do items in HTML5 local storage expire?
...parse(localStorage.getItem("key")),
dateString = object.timestamp,
now = new Date().getTime().toString();
compareTime(dateString, now); //to implement
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...
Pushing an existing Git repository to SVN
...ository, using dcommit. That's all.
Keeping repositories in sync
You can now synchronise from SVN to Git, using the following commands:
git svn fetch
git rebase trunk
And to synchronise from Git to SVN, use:
git svn dcommit
Final note
You might want to try this out on a local copy, before a...
How does `is_base_of` work?
...tness anymore. In an ordinary overload resolution scenario, the call would now be ambiguous because normally the return type won't participate in overload resolution. For conversion functions, however, there is a backdoor. If two conversion functions are equally good, then the return type of them de...
How to undo “git commit --amend” done instead of “git commit”
...happens on top of a different commit from where the current branch head is now.
# Move the current head so that it's pointing at the old commit
# Leave the index intact for redoing the commit.
# HEAD@{1} gives you "the commit that HEAD pointed at before
# it was moved to where it currently point...
Why do we use __init__ in Python classes?
...bute", as opposed to "instance attributes" that are colour or legs above.
Now, to something less canine and more programming-related. As I write below, class to add things is not sensible - what is it a class of? Classes in Python make up of collections of different data, that behave similarly. Cla...
How to insert a SQLite record with a datetime set to 'now' in Android application?
...a couple options you can use:
You could try using the string "(DATETIME('now'))" instead.
Insert the datetime yourself, ie with System.currentTimeMillis()
When creating the SQLite table, specify a default value for the created_date column as the current date time.
Use SQLiteDatabase.execSQL to ins...
mongodb: insert if not exists
... specify what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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How to have an automatic timestamp in SQLite?
...rged your answer and javed's. With DEFAULT (STRFTIME('%Y-%m-%d %H:%M:%f', 'NOW', 'localtime')) one actually gets meaningful microsecond values.
– Dietmar
Jun 22 '17 at 18:24
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