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typeof !== “undefined” vs. != null
...gument, or as a global variable), I think the best way to do it is:
if (my_variable === undefined)
jQuery does it, so it's good enough for me :-)
Otherwise, you'll have to use typeof to avoid a ReferenceError.
If you expect undefined to be redefined, you could wrap your code like this:
(functi...
Any reason to prefer getClass() over instanceof when generating .equals()?
...try must apply, and instanceof makes it very easy to be asymmetric accidentally
– Scott Stanchfield
Mar 3 '09 at 20:15
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JQuery .on() method with multiple event handlers to one selector
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That's the other way around. You should write:
$("table.planning_grid").on({
mouseenter: function() {
// Handle mouseenter...
},
mouseleave: function() {
// Handle mouseleave...
},
click: function() {
// Handle click...
}
}, "td");
...
Numpy index slice without losing dimension information
...y an array that might be length 1 at runtime. For that case, there's np.ix_:
some_array[np.ix_(row_index,column_index)]
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Rails.env vs RAILS_ENV
...hen checking what env one is running in. What's preferred? Are they, for all intents and purposes equal?
5 Answers
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How to sum up elements of a C++ vector?
What are the good ways of finding the sum of all the elements in a std::vector ?
11 Answers
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Dynamically access object property using variable
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You inspired me to create an enhanced version that allows bracket notation & property names with spaces as well as validating the inputs: it.knightnet.org.uk/kb/node-js/get-properties
– Julian Knight
Jan 3 '19 at 14:04
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How fast is D compared to C++?
...
To enable all optimizations and disable all safety checks, compile your D program with the following DMD flags:
-O -inline -release -noboundscheck
EDIT: I've tried your programs with g++, dmd and gdc. dmd does lag behind, but gdc ac...
How to silence output in a Bash script?
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All output:
scriptname &>/dev/null
Portable:
scriptname >/dev/null 2>&1
Portable:
scriptname >/dev/null 2>/dev/null
For newer bash (no portable):
scriptname &>-
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How can you check which options vim was compiled with?
...n without GUI. Features included (+) or not (-):
-arabic +autocmd -balloon_eval -browse +builtin_terms +byte_offset +cindent
-clientserver -clipboard +cmdline_compl +cmdline_hist +cmdline_info +comments
-conceal +cryptv +cscope +cursorbind +cursorshape +dialog_con +diff +digraphs
-dnd -ebcdic -e...