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Dynamically replace the contents of a C# method?
What I want to do is change how a C# method executes when it is called, so that I can write something like this:
9 Answers
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Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
Error: No default engine was specified and no extension was provided
...err }); lines in your code with:
res.json({ error: err })
PS: People usually also have message in the returned object:
res.status(err.status || 500);
res.json({
message: err.message,
error: err
});
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Mediator Vs Observer Object-Oriented Design Patterns
...-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
The Mediator pattern:
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each o...
How to add facebook share button on my website?
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You don't need all that code. All you need are the following lines:
<a href="https://www.facebook.com/sharer/sharer.php?u=example.org" target="_blank">
Share on Facebook
</a>
Documentation can be found at https://developers...
PHP: exceptions vs errors?
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Exceptions are thrown - they are intended to be caught. Errors are generally unrecoverable. Lets say for instance - you have a block of code that will insert a row into a database. It is possible that this call fails (duplicate ID) - you will want to have a "Error" which in this case is an "Exc...
Python matplotlib multiple bars
How to plot multiple bars in matplotlib, when I tried to call the bar function multiple times, they overlap and as seen the below figure the highest value red can be seen only.
How can I plot the multiple bars with dates on the x-axes?
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How to think in data stores instead of databases?
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The datastore makes no distinction between inserts and updates. When you call put() on an entity, that entity gets stored to the datastore with its unique key, and anything that has that key gets overwritten. Basically, each entity kind in the datastore acts like an enormous map or sorted list.
Que...
How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
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Actually you can do this by using the a non hidden function: import operator, operator.add(list1, list2)
– e-satis
Apr 13 '11 at 12:28
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What's the algorithm to calculate aspect ratio?
...re that's been changed from 16:9 to 5:4 - I still remember the incredibly tall, thin cowboys I used to watch in my youth on television before letter-boxing was introduced. You may be better off having one different image per aspect ratio and just resize the correct one for the actual screen dimensio...