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How do I check for null values in JavaScript?
... will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks against -1)) for funct...
Concatenating string and integer in python
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answered Jul 19 '12 at 10:43
user647772user647772
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How do I print the elements of a C++ vector in GDB?
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80
To view vector std::vector myVector contents, just type in GDB:
(gdb) print myVector
This wil...
PHP regular expressions: No ending delimiter '^' found in
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PHP regex strings need delimiters. Try:
$numpattern="/^([0-9]+)$/";
Also, note that you have a lower case o, not a zero. In addition, if you're just validating, you don't need the capturing group, and can simplify the regex to /^\d+$/.
Example: http://ideone.com/Ec3zh
See also:...
How to count items in a Go map?
...ed from the now-retired SO documentation:
m := map[string]int{}
len(m) // 0
m["foo"] = 1
len(m) // 1
If a variable points to a nil map, then len returns 0.
var m map[string]int
len(m) // 0
Excerpted from Maps - Counting map elements. The original author was Simone Carletti. Attribution det...
How can I measure the speed of code written in PHP? [closed]
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10 Answers
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Django: Display Choice Value
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answered Dec 1 '10 at 5:36
jMylesjMyles
9,74466 gold badges3737 silver badges5151 bronze badges
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Matplotlib plots: removing axis, legends and white spaces
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406
I think that the command axis('off') takes care of one of the problems more succinctly than cha...
How to iterate object in JavaScript? [duplicate]
... Neuron
3,54333 gold badges2323 silver badges4040 bronze badges
answered Mar 19 '13 at 10:14
kavinkavin
1,70411 gold badge10...
Swift equivalent for MIN and MAX macros
... JackJack
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