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MySQL check if a table exists without throwing an exception
...PDO syntax for it, but this seems pretty straight-forward:
$result = mysql_query("SHOW TABLES LIKE 'myTable'");
$tableExists = mysql_num_rows($result) > 0;
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HashSet versus Dictionary w.r.t searching time to find if an item exists
...s for Dictionary is so fast that there is no benefit from using HashSet at all, in the OP's case.
– EtherDragon
Jul 27 '12 at 23:03
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How to check for null in Twig?
... Notice: as Twig 2.x check for variable is equal to value like is_ sameas must be {% if var is same as(false) %} not {% if var is sameas(false) %} see Doc url => twig.symfony.com/doc/2.x/tests/sameas.html
– ahmed hamdy
Jul 15 '19 at 17:01
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iOS 7 TableView like in Settings App on iPad
...lor = UIColor.clearColor;
CAShapeLayer *layer = [[CAShapeLayer alloc] init];
CGMutablePathRef pathRef = CGPathCreateMutable();
CGRect bounds = CGRectInset(cell.bounds, 10, 0);
BOOL addLine = NO;
if (indexPath.row == 0 && indexPath.r...
Are there any suggestions for developing a C# coding standards / best practices document? [closed]
...recent AI graduate (circa 2 years) working for a modest operation. It has fallen to me (primarily as I'm the first 'adopter' in the department) to create a basic (read useful?) C# coding standards document.
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How to retrieve checkboxes values in jQuery
...t works (see the example):
function updateTextArea() {
var allVals = [];
$('#c_b :checked').each(function() {
allVals.push($(this).val());
});
$('#t').val(allVals);
}
$(function() {
$('#c_b input').click(updateTextArea);
updateTextArea();
});
Update
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Reading specific lines only
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with linecache.getlin('some_file', 4) I get the 4th line, not the 5th.
– Juan
Dec 11 '14 at 18:14
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What is a lambda (function)?
...us and refers to anonymous functions in programming.
Why is this cool? It allows you to write quick throw away functions without naming them. It also provides a nice way to write closures. With that power you can do things like this.
Python
def adder(x):
return lambda y: x + y
add5 = adder(5)...
Error in exception handler. - Laravel
It's a Laravel-install related question. I have a public-facing Unix server setup:
6 Answers
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Python argparse: default value or specified value
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import argparse
parser = argparse.ArgumentParser()
parser.add_argument('--example', nargs='?', const=1, type=int)
args = parser.parse_args()
print(args)
% test.py
Namespace(example=None)
% test.py --example
Namespace(example=1)
% test.py --example 2
Namespace(example=2)
nargs...