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Compiler Ambiguous invocation error - anonymous method and method group with Func or Action
...roup to a compatible delegate type
(emphasis added) is deeply misleading and unfortunate. I'll have a talk with Mads about getting the word "compatible" removed here.
The reason this is misleading and unfortunate is because it looks like this is calling out to section 15.2, "Delegate compatibi...
Code Golf - π day
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In dc: 88 and 93 93 94 96 102 105 129 138 141 chars
Just in case, I am using OpenBSD and some supposedly non-portable extensions at this point.
93 chars. This is based on same formula as FORTRAN solution (slightly different results t...
Change one value based on another value in pandas
I'm trying to reprogram my Stata code into Python for speed improvements, and I was pointed in the direction of PANDAS. I am, however, having a hard time wrapping my head around how to process the data.
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How to use a variable for the key part of a map
...ivalent to ['a':1]. This can be confusing if you define a variable named a and that you want the value of to be the key in your map. If this is the case, then you must escape >the key by adding parenthesis..
– Michal Bernhard
Mar 2 '16 at 13:10
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How can I see the current value of my $PATH variable on OS X?
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You need to use the command echo $PATH to display the PATH variable or you can just execute set or env to display all of your environment variables.
By typing $PATH you tried to run your PATH variable contents as a command name.
Bash displayed the...
Conditions for automatic generation of default/copy/move ctor and copy/move assignment operator?
... compiler typically auto generates a default constructor, copy constructor and assignment operator.
3 Answers
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Default initialization of std::array?
...zed (C++11 §8.5/11). That includes objects of type std::array<T, N> and T[N].
Be aware that there are types for which default initialization has no effect and leaves the object's value indeterminate: any non-class, non-array type (§8.5/6). Consequently, a default-initialized array of object...
Why does the C# compiler not fault code where a static method calls an instance method?
...C# 7.3 (May 2018). In What's new in C# 7.3, the section Improved overload candidates, item 1, it is explained how the overload resolution rules have changed so that non-static overloads are discarded early. So the below answer (and this entire question) has mostly only historical interest by now!
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Check if item is in an array / list
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@jdi, and that loop will run much faster than the one coded explicitly in Python, not to mention being easier to read.
– Mark Ransom
Jun 28 '12 at 19:44
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Select something that has more/less than x character
...e documentation:
http://www.techonthenet.com/oracle/functions/length.php
And here is the mySQL Documentation of Length(string):
http://dev.mysql.com/doc/refman/5.1/en/string-functions.html#function_length
For PostgreSQL, you can use length(string) or char_length(string). Here is the PostgreSQL d...