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What's the false operator in C# good for?
... allow for nullable boolean types prior to the Nullable (i.e. int?, bool?, etc.) type being introducted into the language in C#2. Thus you would store an internal value indicating whether the value is true or false or null, i.e. in your example >0 for true, <0 for false and ==0 for null, and t...
Simple logical operators in Bash
...nds are executed in a separate subprocess, so any redirection, assignment, etc. performed inside the parentheses has no effect outside the parentheses.
With a leading dollar sign, $(…) is a command substitution: there is a command inside the parentheses, and the output from the command is used a...
Difference between Lookup() and Dictionary(Of list())
...alue>, which means that it's efficient to use with Count(), ElementAt() etc.
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bool operator ++ and --
...R TRUE is TRUE, x OR FALSE is x, x AND FALSE is FALSE and x AND TRUE is x, etc using the same operators for boolean and bit-wise operations (since VB assumes twos-complement so -1 is all 1 bits). However, this can cause some strange bugs in VB if the coder doesn't catch that 2 (true) AND 4 (true) re...
Add data annotations to a class generated by entity framework
...an read the rules for validating each field (from a database, config file, etc.) and add validators as need be. It has the added values that your validation is no longer tightly coupled to the model and can be changed without need to even restart the site. Of course it might be overkill for your cas...
Does C# have extension properties?
...nage internally dictionaries and it could be difficult (memory management, etc...).
For this, you can still use the TypeDescriptor/ConditionalWeakTable technique described earlier and with the property extension, hides it under a nice property.
Syntax is still subject to change as implies this issu...
How does collections.defaultdict work?
...interesting when the values in a dictionary are collections (lists, dicts, etc.) In this case, the value (an empty list or dict) must be initialized the first time a given key is used. While this is relatively easy to do manually, the defaultdict type automates and simplifies these kinds of operatio...
How to exclude a directory in find . command
...since -deletewill first delete the leaves, then the parents of the leaves, etc... But for specifying -prune to make sense, find needs to hit a directory and stop descending it, which clearly makes no sense with -depth or -delete on.
Performance
I set up a simple test of the three top upvoted ans...
How is a tag different from a branch in Git? Which should I use, here?
... each branch that you may want to recreate -- for delivery, bug diagnosis, etc.
It's actually more complicated than this -- or as complicated as you want to make it -- but these examples should give you an idea of the differences.
...
How much size “Null” value takes in SQL Server
...like nvarchar(max) varchar(max) Null will takes 0 bytes and for int, chars etc it will take the default size to default values they have ?
– Rocky Singh
Sep 16 '10 at 22:10
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