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In a Bash script, how can I exit the entire script if a certain condition occurs?
...script in Bash to test some code. However, it seems silly to run the tests if compiling the code fails in the first place, in which case I'll just abort the tests.
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If table exists drop table then create it, if it does not exist just create it
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Just put DROP TABLE IF EXISTS `tablename`; before your CREATE TABLE statement.
That statement drops the table if it exists but will not throw an error if it does not.
s...
Find the index of a dict within a list, by matching the dict's value
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tom_index = next((index for (index, d) in enumerate(lst) if d["name"] == "Tom"), None)
# 1
If you need to fetch repeatedly from name, you should index them by name (using a dictionary), this way get operations would be O(1) time. An idea:
def build_dict(seq, key):
return dic...
UITableView load more when scrolling to bottom like Facebook application
...th *)indexPath
{
// Classic start method
static NSString *cellIdentifier = @"MyCell";
MyCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (!cell)
{
cell = [[MyCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:MainMenuCellIde...
What .NET collection provides the fastest search
... answer to "What is the fastest searchable collection" depends on your specific data size, ordered-ness, cost-of-hashing, and search frequency.
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Is there a simple way to delete a list element by value?
I want to remove a value from a list if it exists in the list (which it may not).
21 Answers
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Check if a number has a decimal place/is a whole number
I am looking for an easy way in JavaScript to check if a number has a decimal place in it (in order to determine if it is an integer). For instance,
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Delete an element from a dictionary
..., and also using linear space. For small dicts, this is not a problem. But if you're planning to make lots of copies of large dicts, you probably want a different data structure, like a HAMT (as described in this answer).
sh...
How expensive is RTTI?
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Regardless of compiler, you can always save on runtime if you can afford to do
if (typeid(a) == typeid(b)) {
B* ba = static_cast<B*>(&a);
etc;
}
instead of
B* ba = dynamic_cast<B*>(&a);
if (ba) {
etc;
}
The former involves only one comparison of s...
Javascript sort array by two fields
...ve code sorts the array by gsize - smallest to largest. It works good.
But if the gsize is the same I would like it to then sort by glow.
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