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Why exactly is eval evil?
...tors:
(let ((ops '(+ *)))
(dolist (op ops)
(print (eval (list op 1 2 3)))))
That's better written as:
(let ((ops '(+ *)))
(dolist (op ops)
(print (funcall op 1 2 3))))
There are lots of examples where beginners learning Lisp think they need EVAL, but they don't need it - since expressi...
Is 'float a = 3.0;' a correct statement?
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It is not an error to declare float a = 3.0 : if you do, the compiler will convert the double literal 3.0 to a float for you.
However, you should use the float literals notation in specific scenarios.
For performance reasons:
Specifically, consider:
float fo...
What does the “map” method do in Ruby?
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432
The map method takes an enumerable object and a block, and runs the block for each element, out...
jQuery map vs. each
...you can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. F...
Dealing with multiple Python versions and PIP?
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23 Answers
23
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Could not find com.google.android.gms:play-services:3.1.59 3.2.25 4.0.30 4.1.32 4.2.40 4.2.42 4.3.23
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edited Dec 3 '15 at 1:20
CJBS
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a...
Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3 [duplicate]
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3 Answers
3
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Twitter bootstrap 3 two columns full height
I'm trying to make two-column full-height layout with twitter bootstrap 3. It seems that twitter bootstrap 3 does not support full height layouts.
What I want to do:
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Python - How to sort a list of lists by the fourth element in each list? [duplicate]
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unsorted_list.sort(key=lambda x: x[3])
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Why am I getting a “401 Unauthorized” error in Maven?
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JohnJohn
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