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Check if $_POST exists
...return a blank value.
If your $_POST is coming from a user-inputted field/form and is left blank, I BELIEVE (I am not 100% certain on this though) that the value will be "" but NOT NULL.
Even if that assumption is incorrect (someone please correct me if I'm wrong!) the above is still good to know ...
Can JSON start with “[”?
...eroperable in the sense that all
implementations will accept these as conforming JSON texts.
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How to change CSS using jQuery?
...ar things up a little, since some of the answers are providing incorrect information:
The jQuery .css() method allows the use of either DOM or CSS notation in many cases. So, both backgroundColor and background-color will get the job done.
Additionally, when you call .css() with arguments you ha...
Logic to test that 3 of 4 are True
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Long but very simple, (disjuntive) normal form:
(~a & b & c & d) | (a & ~b & c & d) | (a & b & ~c & d) | (a & b & c & ~d)
It may be simplified but that requires more thinking :P
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Should I size a textarea with CSS width / height or HTML cols / rows attributes?
Every time I develop a new form that includes a textarea I have the following dilemma when I need to specify its dimensions:
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What is the difference between sed and awk? [closed]
...e, you could replace all the negative numbers in some text that are in the form "minus-sign followed by a sequence of digits" (e.g. "-231.45") with the "accountant's brackets" form (e.g. "(231.45)") using this (which has room for improvement):
sed 's/-\([0-9.]\+\)/(\1)/g' inputfile
I would use aw...
What does “use strict” do in JavaScript, and what is the reasoning behind it?
...e x;)
Forbids binding or assignment of the names eval and arguments in any form
Strict mode does not alias properties of the arguments object with the formal parameters. (i.e. in function sum (a,b) { return arguments[0] + b;} This works because arguments[0] is bound to a and so on. )
arguments.call...
Invalid argument supplied for foreach()
... an error, it might cause another one.
Be aware: If you expect a specific form of array to be returned, this might fail you. More checks are required for that.
E.g. casting a boolean to an array (array)bool, will NOT result in an empty array, but an array with one element containing the boolean...
How can I “disable” zoom on a mobile web page?
I am creating a mobile web page that is basically a big form with several text inputs.
10 Answers
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Print a list in reverse order with range()?
...nd, but it needs to be range(10), not range(9). Also, if you want a fully-formed list (for slicing, etc.), you should do list(reversed(range(10))).
– John Y
Sep 2 '11 at 16:49
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